Recurrence in same spot suggests hemorrhoid or herpes, perhaps an anal fissure. Anal sex is inherently traumatic compared with vaginal or oral intercourse. But STDs are possible. Get it checked out.
HHH, MD
sorry... 3 weeks ago involved protected sex where there was anal contact. there was a very small amount of bleeding after and there was discomfort for a few days. it was my first time receivng anal and i don't know if that would cause any problems.
i kind of recall a "bump" in that same spot many months ago - again, just one and not painful.
thank you again
Rectal area sores and bumps are commonly due to both STDs and non sexually transmitted causes, like hemorrhoids, anal fissures, etc. I just can't say more from your description; information about precise location (front, back, or side of the anus), size, etc. might give a clue. You also don't say whethcr you are male or female, and whether your sex 3 weeks ago included penile insertion into your rectum. All those would influence the probabilities. But regardless of those details, my central advice is for you to see a health care provider. Your local health department STD clinic would be a good place to start if you don't have your own regular doctor, or are concerned that s/he isn't likely to be knowledgeable about STDs.
Good luck-- HHH, MD