Do you have bloody stools where the blood is mixed in? (generally crohn's colitis tends to diarrhea rather than constipation, but you do find a few with constipation)Are you losing weight all out of proportion to what you are eating?Was your sedimentation rate elevated on any blood tests when you had symptoms?Do your symptoms calm down at night or do you get woken up with pain from a sound sleep (when you are sleeping)?That you feel better after a BM tends to indicate IBS. So far nothing you mentioned really sounds like it has to be something other than IBS. IBS often starts after a bout with the stomach flu.I know it can be hard not to worry that it is something worse than IBS, but try to relax and calm the anxiety down. Stressing out will make the symptoms worse than they would be on their own.K.