You didn't say how old you are or if you're male or female... It could possible be two things that I know of...
When I was growing up and played a lot of sports, I would get ingrown hairs down around my anus. I went to the doctor several times for a painful bump like pimple spot that hurt when I walked, played sports and even wiped. He said they were ingrown hairs.
Apparently my jock strap would ride high into my ass crack and do havoc on my ass hairs and also rub my anus area raw. I used the have to use anti-bacteria soap and a scrubby and scrub that area when I showered and put some cream stuff on it at night. It could turn into a cyst if not watched and cared for he said. If your doctor appointment is not for a few days and you think it will subside a little before then, I suggest snapping a few digital snapshots of it for him to see…
Let us know how it turns out…
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-Roc-
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