I've had these problems as long as I can remember -- as a little kid, I had stomach aches all the time and spent long periods of time in the bathroom.
It sucks to have IBS, so that's not lucky, but at least you know what you have and can address it!! I am 29 now and just found out fairly recently that what I have is not something unique to me and that there are ways of dealing with it. So hopefully by having to deal with it so young, you will figure out your triggers sooner and it won't seem like so much of a burden.