sounds to me like your butthole is falling out... its possible! i am a male nurse & have seen it/dealt with it many times with patients. you may need to go to doctors because if it goes untreated you may get an infection. also, to keep it from happening again, i would perform an enema (look up the definition) and substitute monster energy drink instead of water for the enema. Its very good for the body and soul
It's something that you need to see your doc about. it could be a 'simple' hemorrhoid, however it's always better to check it out to be sure. Hemorrhoids can often be caused by pushing if you're having problems trying to defecate, but they can also be cause by bouts of diarrhea.