I remember everything about my first headache. I was lying in bed, the sun streaming through the gauze curtains, feeling deliciously relaxed after a tryst with my boyfriend.

Suddenly I noticed that I couldn't focus with one of my eyes; there were strange kaleidoscopic wheels dancing wherever I tried to look.

Then it hit, like a bomb of black ink in a clear glass of water. It hung there for a few seconds before exploding into pain.

That was the beginning. For the next few months my punishment for sex was a headache that forced me to retire from life. The pain was so intense I went to see a specialist to check that I didn't have an aneurysm. He told me I had two separate headaches going on. The visual disturbance was a migraine but the headache alone was “just a headache” probably caused by stress and tension.

That anything could be “just a headache” will elicit an anxious and knowing response from sufferers. There are thousands of different classifications. Apart from migraines, which themselves have many variations, there are chronic daily headaches, rebound headaches (which come from the overuse of painkillers), tension headaches (a lot more painful than the name suggests) and, worst of all, cluster headaches (which are so excruciatingly painful that sufferers sometimes commit suicide).

Soon my headaches occurred about once a month and no longer seemed to be linked to any particular activity. They would hit me out of the blue and meant I couldn't work for the rest of the day.
My specialist recommended physiotherapy, and while the physio I went to didn't give me any relief, I did find temporary salvation in the form of Gerry Gajadhar-singh, a Harley Street osteopath.

He told me my muscles were so tense down one side of my body that I risked serious long-term problems if I didn't correct them. I didn't think of myself as being particularly stressed. I had my own fashion business, which involves being pressurised most of the time, but I was good at appearing calm. So it was coming out in my body. Drat.

Gerry's main recommendation was regular Pilates, to which I dutifully went for ages — and my headaches stopped. It was wonderful being headache-free, but instead of nurturing this new status I became complacent and stopped going. My headaches returned.

Eight years on from my first attack, my headaches arrived more frequently — sometimes three times a week — and with greater ferocity than ever before. My muscles set into tortured patterns that were immune to Pilates. Not only were there headaches, debilitating and extreme, there were semi-headaches: the piercing nail through the crown of my head; the feeling that a piano wire was being stretched from behind my right eyeball.

Added to this, I had a newborn son and an interesting new job revamping an old English retail house. Now that I wanted to exercise the pain away, there was no time to do so. In vain hope, I started to investigate all possible dietary triggers.

I had long since cut out wheat. Next to go was dairy, which helped with the general feeling of sluggish toxicity in my gut, a companion of the migraine-type headache. But the reactions were wildly inconsistent. I could eat chocolate and be fine — and then suddenly not be fine. The same with coffee, sugar and any of the other things I loved and craved. In desperation I ended up with a huge list of no-go food and followed a mostly macrobiotic diet. I became the nightmare dinner guest.

The next manifestation of human bondage was travel. Plane journeys spelt immediate suffering. I'll never forget the awfulness of one flight to Thailand or the time I was upgraded to Virgin Upper Class only to spend the journey shielding my eyes from the light and begging the stewardess for another complimentary hand massage.

I tried to outwit my headaches but they got their own back. They would return at the weekend and I would creep into bed, draw the curtains and watch ruefully as my husband and child trooped off for another day without me.

After five years of osteopathy, diet management, acupuncture, reflexology, homeopathy and paracetamol, I'd wrestled my headaches down from three a week to one every fortnight. Then one day I tried a beauty treatment where my face was injected with carbon dioxide intended to dramatically improve the complexion. It may have been chance, but the said treatment coincided with some of the worst headaches of my life. I felt as though a bonfire of poisonous waste had been started in my shoulders and the hot, revolting fumes were trapped in the crown of my head. I had never felt scared by my headaches before. Now the thought of getting on a plane made me want to cry.

Then I discovered Dr Dermot O'Flynn, an NHS and private GP with 20 years' experience who runs a headache clinic for difficult cases. I felt a surge of hope when he told me he had suffered from migraines for years — he had even experienced a hemiplegic headache where he temporarily lost the use of one side of his body — and cured himself through decaffeination. Dr O'Flynn has a holistic approach to healing and explained what could be happening to me and how I could deal with it by drawing a clock pointing out all the contributing factors that push the hand around to “headache time”.

A typical “clock” might start with stress, followed by tiredness, missing a meal, sugary food, falling caffeine levels, emotional upset, muscle tension. The “clock” is a useful way to look at your symptoms and work out what you can deal with.

He insisted decaffeination was essential — falling caffeine levels are a major trigger for all headaches — and prescribed a painkiller called Migramax, which suppresses the headache before it manifests.

He also prescribed me Amitriptyline in liquid form, so I could take a very low dose (2mg). In a high dose it is an antidepressant but in lower doses it is used for chronic-pain management. I was reluctant to take anything so powerful but he explained that it would help me sleep deeply and give my body a good rest and slow down the headache “clock”.

The Migramax worked a treat, reducing what might have been a killer attack to a couple of hours' sleep. And the Amitriptyline made me feel the furnace stoking my headaches had been put out and that the evil puppeteer controlling my hunched shoulders had gone on holiday.

The hardest thing was giving up my precious cups of tea. But I got over it. During the next few months I mailed my progress to Dr O'Flynn and gradually lowered my Amitriptyline to 1mg. But if I forgot to take it one night, or lowered it too fast, I would feel the heat start up in my shoulders; the beast was small, but still there.

Then, by chance, I had a conversation with a friend who told me her headaches had disappeared when she'd had her mercury fillings removed. My blood tests had shown a high level of mercury in my system but it was without much expectation that I booked in to see David Hefferon at the Ella Clinic in Harley Street.

In the weeks that followed, Hefferon replaced my seven ancient mercury fillings, two at a time. I didn't think about it much until about a month after they were all gone, I forgot to take my Amitriptyline one night but found I slept well and woke feeling fine. I tried again the next night, and the next. No heat in my shoulders, no headache. It was as though some fetid, rotten thing had left my body.

So delighted was I with the results that after replacing my fillings I decided to do the same with my expensive crowns. I haven't had a full-on headache since November 2007, and if I do get one, its daintiness almost makes me laugh. My energy levels have rocketed.

I am convinced I found a cure in getting rid of the mercury. I haven't even used my last Migramax prescription, as it doesn't figure as the most important item in my handbag any more. My diet is much more relaxed, though on my birthday I ate treacle sponge with cream and Turkish sweetmeats all afternoon, and I was punished with a headache that lasted all night — but it was nothing compared to the old days.

Instead of having a big, butch, monster headache jailer, I now have a little leprechaun.

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