could be a hemorrhoids needs local examination

It's in 11 o Clock position, it's a Hemorrhoids, patient needs proctoscopy to confirm the diagnosis and to check other positions also.

Could be fistula in ano/haemorrhoids. Needs proper proctoscopy examination to determine exactly what is it.

A recurring swelling in the anal region like a boil, disappearing and then returning months later—is highly characteristic of a perianal abscess or an underlying anal fistula. Even without common bowel symptoms like constipation or visible blood in the stools, recurring lesions in this specific area require evaluation by a healthcare professional, such as a colorectal surgeon or general surgeon, because they rarely resolve permanently on their own

• Perianal Fistula (with a temporary blockage): This is one of the most common reasons for a bump near the anus to repeatedly appear and disappear. A fistula is a small tunnel connecting an internal gland inside the anus to the external skin. When the external opening heals over or gets blocked, fluid or mucus builds up underneath, creating a smooth, "boiled bubble" swelling. When the pressure causes it to drain internally or microscopically, the swelling completely vanishes, only to reform later when the tract closes again. Please consult a General Surgeon for examination and management.

Its due to the constipation

Hello.. this could be external hemorrhoids. Or it could be a perianal abscess . is it painful ?? If yes. Then you should get it checked from a general surgeon nearby

It looks like external hemorrhoids or piles. But it may be perianal abscess. Need to be checked by a surgeon to clearly differentiate. Avoid prolonged sitting.

Based on your description, the recurrent swelling near your anus could be due to an external haemorrhoid (pile), a perianal cyst, or occasionally a perianal abscess or fistula. Since the swelling disappeared on its own and has now reappeared, it is important to identify the exact cause. The absence of bleeding, constipation, or pain is reassuring, but these symptoms are not always present in anorectal conditions. I would like to know a few details: 1. Is the swelling painful or completely painless? 2. Is it soft or firm when touched? 3. Does the swelling increase in size during or after passing stools? 4. Have you ever noticed pus or fluid discharge from the swelling? 5. Is the swelling appearing at exactly the same location as before? I would recommend a physical examination by a general surgeon to confirm the diagnosis. If a fistula is suspected, further investigations such as MRI fistulography may be required. Meanwhile, avoid squeezing the swelling and maintain good perianal hygiene. If you develop severe pain, redness, fever, or rapidly increasing swelling, seek medical attention promptly.

Image you have enclosed showing it might be Hemorroids According to your history swelling appeared first and later disappeared indicates it to b a skin tag or else a Sentinel pile. One more thing blood in stool indicates either of bleeding pile / Fissure in Ano It requires proctoscopy examination and management According to findings