Every day, the same thoughts race through my mind: "Will it be my last?" "Is my heart beating OK?" "What does that ache mean? It must be something bad, mustn't it?" As soon as I wake up, I'm exhausted by all the scenarios that plague me.

I have struggled with anxiety for 14 years, but for the past four it has manifested itself into a feeling that something is wrong with me - something really bad - and that I am going to die. I'm extra-sensitive to every little twinge. At first I was certain I had a brain tumour - the daily headaches and dizziness were a sure sign of something sinister. The doctor put it down to tension, but that didn't reassure me. I pestered him every week until he sent me for a CAT scan. The two-week wait for the results was torture - I had decided that if the doctor thought my symptoms warranted a scan, there must be something wrong.

When it came back clear, a weight lifted from my shoulders; I wasn't going to die. Then, a few weeks later, my chest began to ache and anxiety stole in again. What could it be but a problem with my heart? I grew afraid to go out in case it made my heart beat faster. My fear was it could bring on on a heart attack. I checked my pulse all the time and visited my dad to use his blood-pressure machine. If the reading wasn't in the right parameters the first time, I'd check again and again until it was.

The doctor said the pain was due to a strained chest muscle, and that increasing my heart rate increase would actually make it healthier. Hearing his words, my rational side knew it made sense. He is very sympathetic, and always says I can see him for reassurance. He says my symptoms are due to anxiety, and has put me on the waiting list for cognitive behavioural therapy.

In my heart, I know this is true. Being so tense does have a physical impact. Still, at home, typing my symptoms into the internet, all rationality goes out of the window. Google is my worst enemy, but it's so addictive. It always suggests the worst-case scenario. A cold becomes pneumonia; a cough lung cancer. I'd spend hours and hours searching for answers, terrifying myself with gory pictures. They call it cyberchondria.

Then I came across a forum on health anxiety and realised that this is what I have. Now I try to limit my surfing to anxiety forums, to try to keep a lid on my health worries.

Sometimes I ask my husband, Ernie, if he ever gets the same aches or pains. He says he doesn't, but then he never complains about being ill. He's more worried about normal things such as the credit crunch. He calms me down and reassures me a lot. So when he got stomach pains earlier this year, it threw me into a mad panic. He dismissed them as nothing, but that old familiar feeling of dread came over me and, coupled with my medical knowledge from the internet, I knew it couldn't be something he'd eaten. He was rushed to hospital, where they found he had a perforated bowel and needed emergency surgery or he'd die.

I went into meltdown. My grandmother had died from this, and Ernie was my rock. As I sat waiting for him to have a scan, I felt my heart drumming violently in my chest. It became unbearable. I went to A&E, certain the heart attack that haunts my thoughts was finally happening. An ECG showed it was just a panic attack.

I've had two courses of counselling, but they helped only temporarily. I can't see why talking about my past would change things. My mum was very protective of me as a child - for example, she didn't like me to blow up balloons in case I choked - but she had a common-sense approach to health and never let me fake an illness to stay off school.

I know I'm a bit of a contradiction. Worrying about my health dominates my thoughts, yet I don't eat very healthily and smoke five to 10 cigarettes a day. I know I should exercise, but I don't like my heart to pound. I don't have children yet - if I did, I worry I would pass my fears on to them.

My job as a tourism promotions officer does help to distract me, and my colleagues are very understanding. I'm quite open about my health anxiety. I couldn't hide it because it's written all over my face.

I feel guilty about moaning about myself when other people really are ill. I'm only 32 and I yearn to be more carefree. I know I have a core of inner strength, if only there were a magic pill that would make me better.

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