Can't Eat - Results In Stomach Ache & Diarrhea?

Since yesterday around 2am I had the runs after I woke up. That night I had it two more times and that day I had it another couple times. Today I've had it a few times now. I haven't been able to eat anything since yesterday (besides bites of toast and light stuff) because it causes the worst stomach ache and then I get the runs. I'm not sick and have no other symptoms. I'm hungry as hell too but the stomach pains and diarrhea keep me from eating. It only happens right after I eat something. What should I do?? What should I eat??