Hi. Thanks for your query and an elucidate history. You are getting this problem either due to a surgical condition like appendicitis or diverticulitis which gets aggravated sometimes.. Another possible reason is that you may suffering from a condition called irritable bowel syndrome.. IT is always a better idea to get an opinion and clinical examination by a Gastroenterologist, to undergo the investigations as per his orders. I would suggest you to undergo contrast enhanced CT scan done along with ultrasonography and color doppler studies.