Almost everytime i eat, i get a pain in my lower stomach, feel sick, and have diareah. what could this be?

Maybe IBS: Irritable bowel syndrome seems to be more and more common these days...Symptoms may vary, but typically include bloating, gassiness/flatulence, cramping, constipation/diarrhea(could be alternating), easily full sensation with meals, may be nausea etc...Stress can make the symptoms worse... Aerobic exercise, stress relief, and regular pattern in diet can help....But you should consult your doc....

IBS: If this is a chronic problem rather than a viral gastroenteritis of a few days duration, then i suspect an irritable bowel problem. As soon as the meal reaches the stomach an exaggerated reflex starts waves going down the intestines causing cramps and urgent bowel movements. If this is so, your physician could prescribe an antispasmodic medication 1/2 hour before the meal to modify the reaction.