Pain in bone. Friction or bowel issues?

I am feeling pain in the bone situated back of anus. It is mainly between the buttocks. If i press the buttocks from the upper portion close to each other upon standing i feel pain sometimes. I experienced that when i have a bowel movement then the pain reduces and sometimes go away. The pain is not constant it starts if i get into squatting position or just sit and get up or if i apply pressure to the area. I am undergoing digestive issues since march and had problem of stool retention for which i am taking medicine and after that the problem is bit resolved but the pain in bone portion starts often. I don't have any history of falling on bone or cysts etc. But i notice everytime i take bath that a bunch like something of cotton threads of undergarment and hairs is present always. Can the pain be due to friction or bowel issues?