What Causes Rectal Pain?
Thrombosed rectal veins
Detailed Answer:
Hi,
It is usual for people who had past history of hemorrhoids to have recurrence. Sometimes these may not be visible to the naked eye. Since the colonoscopy was normal I would subject the issue to IBS and / or anal fissures.
The rectal veins get thromobosed to cause pain and adding fuel to the fire is IBS where may have alternative constipation or diarrhoea. I suggest you to get anoscopy as well to check for anal fissures.
Usually Prep H gives you relief if not sitz baths with antiseptic lotions thrice a day would be helpful. There are other prescription medications that your doctor can prescribe for pain relief. You can take over the counter pain preparations like Motrin as well before bed time. It is good to have sitz bath before bed time so that you do not have to wake up in the middle of the night with pain.
Hope this helps.