I am in high school and i have been running year round for a few years. I run about 50 miles a week and i feel fine most of the time. However, recently i have been having horrible stomach pains while running. I eat healthy and drink plenty. I give myself at least 3 hours to digest before i run. However, without fail my stomach aches and after about 5 or 6 miles i feel like i might just go to the bathroom in my short-shorts. I am forced to stop and walk. It is horrible and seriously impacts my running. Please help, this is becoming a serious problem. Any and all suggestions are welcome.

I also am not releasing solid waste after these experiences, it is almost like i have diarrhea, except that this has happened before and i usually just wait it out.