Thank you for the query.
Your symptoms might be caused by anal fissure
. It is very common that this is not visible in the colonoscopy
as the verge of rectum
is rather not watched by a doctor who performs it. To have it diagnosed, it is necessary to have simple rectal exam by someone who knows what to look for.
To have it treated you should get rid of hard stool with soups and more water intake. Fiber rich foods should improve it as well. It is very important to not push hard on stool as this tears the rectum. Hot baths with Quercus Cortex can help as well. You should also ask your doctor about Nitroglycerin
Gel and Xylocaine
Gel. Such treated fissure should get healed in a weak or so.
Hope this will help.