I get diarrhea after eating foods that never bothered me before. the fit only last one or two times then corrects itself. what's wrong with me?

Needs More Eval: Our body's response to what it comes in contact with is dynamic & changing. It can involve multiple factors including immune & nervous systems & inflammatory pathways. Its possible to develop sensitivities & intolerance to foods that one did not have previously. I often start with a food/symptom diary, food sensitivity testing & stress vs 'mindful eating' practices & maybe probiotics & enzymes.

IBS: Sounds like irritable bowel syndrome. Have your discussed this problem with your primary care physician?