Im really really scared. First of all im not sexually active, so its not a STD. Sometimes, when i have diarrhea or a problem going to the bathroom a bump that is like a bubble covered in skin will appear, its weird because it starts from the end of the part in which my labia minora end (where they join) and then it finishes in my anus. The thing is that it is painful, it aches when i go to the bathroom and when i move, but as i said its temporally, and it normally appears when i am on my period.