Why am I craving cigarettes?

I tried a cigarette years ago and that was the only time I've ever smoked and im talking one puff. For the past week Ive been wanting a cig so bad and I dont know why, my friends smoke but ive never wanted to be a smoker and still dont want to be, i thought this phase would just p but its all i can think about which is quite pathetic really, been chewing gum to try and forget about it. Shall I just have one and remember how disgusting it was because im starting to p!ss myself off!!