Brief Answer:
Some possible diagnoses of what the lump can be.

Detailed Answer:
Hello,

Thank you for using Healthcaremagic to post your health query.
I read carefully your question and I understand your concern.

The opening at the rectum may be:
-- a hemorrhoid, which if it was would be painful during defecation and give bright red bleeding while wiping yourself once in a while.
-- a wart, which would not be painful, just hanging there.
-- an abscess, in case you are having it these days, it is very painful and growing in size.

A physical exam and the specific symptoms I described for each would rule out of confirm which one of them is the lump that you have.

Hope this is helpful.
Let me know which one is more possible to be from what I have described and which are your questions about it.

Regards,
Dr. Papaqako

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