<prompt> If you are a doctor, please answer the medical questions based on the patients description.Hi, my fiance just got over the flu last night.when I woke up this mOrNing I had really bad stomach cramps like I needed to poop and I cant.my butt hurts and I did thrOw up the ford from the night before so I dont know if its the flu or food poisoning, but my butt hurts and its giving me stomach cramps bad.isit normal  <response>: Hi. This may be due to gastroenteritis food poisoning. Could occur as the body resistance goes down due to preexisting flu. The pain in the anal region can be due to parotitis as part of gastroenteritis. I would advise you the following. Get physically examined and for the vitals from your Doctor as you have to get a prescription for treatment. Antibiotic, metronidazole, risperidone and PPI; also take probiotics, activated charcoal tablets, banana with curds, a plasmolytic. If you do not get results with this, you may need further investigations to rule out any underlying cause like diabetes or so. 