You have to be seen. If your doctor won't address this, get a new one. I can't believe he didn't order a stool sample, easiest test in the world. They can test for hidden blood, pathogens, etc... You may need a scan of some type. If you have an adequate fiber intake, your stools aren't hard, and you are stooling....constipation is not the problem. White mucus is not the most important issue The severe pain when defecating is. Make an appointment with a different doc, yeah ER is not the place.