stomach problems

[collegegirl235]

I'm 18 years old and for about a year now iv been having horrible stomach problems. after everything i eat i have to go to the bathroom, and if its a full meal its usually always diarrhea that lasts the rest of the day.  i'v stopped going out to eat with my friends because i would have to run home right after. i started to wake up 3 hours before class so i can be abe to eat breakfast and go to the bathroom fully b4 i have to leave. i panic if i have to go out of town or even to class for a few hours because i cant conrol my stomach. the doctor has no answer for me and i have tested negative for ibs. please help.

[collegegirl235]

yes i had blood and stool tests and they were negative

[mammo]

How were you tested for IBS?  This is what it sounds like to me.  Did they do and endoscopy and colonoscopy to rule out any physical problems?  Any bloodwork?