I got drunk off my moms cooking brandy around 15, and soon tried pot after that, but didnt inhale correctly the first few times. When I actually did get stoned for the first time I thought I had opened my psche to demons (had an odd upbringing) and really freaked out, but soon caught on. Cigs soon followed.
My earliest memory of intoxication was when I was 8 at a friends house. and he told me to take a deep breath of some ammonia, and I got a fat head rush.