When I was young, I had everything I needed, but I wanted more. My head was turned by the glamour of music videos and I felt I wouldn't be happy until I had £90 trainers. My mum and dad couldn't afford them, so I started dealing ? it was all around me on the estate in London where I grew up. I began with cannabis in my early teens and by the time I was 16, I was selling class A drugs.

The money started rolling in and I enjoyed the lifestyle. I suppose we were in a gang, but to me they were my childhood mates; I loved them.

Guns were readily available and part of our day-to-day life. We were young and foolish, and a silly accident was bound to happen. One day, my friend was playing around with a gun, aiming it at me as a joke. He assumed it wasn't loaded but there was still a bullet in the chamber and when he pulled the trigger, I got shot in the head. I was terrified, as was he. I was rushed to hospital and the doctors discovered that the bullet had travelled only a few millimetres inside my skull ? they thought that because it was from a replica air rifle, it hadn't made the impact a bullet from a real gun would have done. Amazingly, I was absolutely fine. After 24 hours I was discharged, with the bullet still in there ? removing it may cause nerve damage, so it will probably be there for the rest of my life.

At the time, it didn't really bother me. In my world I often came into contact with danger and I'd learned to let it wash over me. I felt fine and within days I was back on the streets. Instead of seeing my gunshot wound as a warning about my precarious lifestyle, I chose to carry on as usual. I felt that I was living the high life. My parents have strong moral values and were very shocked when they discovered what I'd been up to, but I didn't give it a second thought.

With hindsight, I realise that the future held only two options for me: death or jail. Fortunately, my fate was the latter. Aged 19, I was in south London, dealing drugs as usual, when I was approached by a police officer and searched. The police found drugs on me and I was arrested and put on bail, pending a two-year prison sentence for supplying class A drugs.

Everything changed while I was waiting for my sentence. I went on a trip to Kenya, organised by Regenerate, a charity that takes young people from British estates to developing countries to help street children. While I was there, I appreciated how exceptionally lucky I was to live in the UK, with the NHS, free education, comfortable housing. My parents had moved here from Pakistan to give me a better start in life, and I had been throwing it all away. I gave the African kids my clothes and the tiny sum of money we'd raised ? the pleasure it gave them was amazing.

Prison reconfirmed the pointlessness of my previous lifestyle. I saw men in their 40s who had been in jail repeatedly, and it hit home that this was all I was facing unless I radically changed my life. I had a baby son, Khalil, to whom I hadn't really paid much attention. I resolved to make time for him; I didn't want his childhood memories to include visiting his father in prison.

I became a model prisoner, studying hard and passing exams. I was transferred to an open prison and, on day release, I worked with an entrepreneur who encouraged and mentored me. After prison he suggested I apply for a postgraduate business course at Cambridge University. I was completely underqualified but they gave me a chance. It was intimidating on the first day, but I was transparent about my past and my inexperience, and everyone was very supportive.

Although I was determined that I wouldn't return to my old life, it was still a relief that most of my friends were in prison. It meant that I could distance myself from them ? we're still in touch, but they know I've changed. When they come out, if they decide to give up dealing, then I'll support them in any way I can ? if not, then we can't be in communication.

Sometimes I look at the tiny scar above my eyebrow and remember my time as a drug dealer, and how casual we were around guns, and I shudder.

? As told to Emily Cunningham

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