Hello and welcome to healthcaremagic I have read your question and i can understand your concerns. If were treating you in my clinic i would have examined your anal region to look for perianal hematoma.it is also known as external haemorrhoid.these occur due to accumulation of blood or dilation of small veins below the dentate line of anal canal..In this case i would have evacuated the haematoma by surgical incision. I would also ahve looked for anal fissure which is a cut in the lower part of anal canal and very painful.chronic fissure cause lump in the form of skin tag.for this i would have suggested glyceryl trinitrate cream..surgery like lateral internal sphencterotomy is needed in chronic case. In the abscence of both above mentioned condition i would have done digital rectal exam to look for haemorrhoids.4rth degree haemorrhoids can become thrombosed and can cause pain also. I would suggest you to meet a general surgeon for second opinion. Thanks. Hope the answer is helpful. Keep asking us at hcm. Regards