Have you looked to see if you can see anything? There are so many things if MIGHT be. An absess forming, a fissure, a hemorrhoid...
Best thing to do is let your dr know and see if he sees anything. Meanwhile, try taking sitz baths and see if that helps or brings something to a head.
Dx'd w/ Crohn's in 1979 at age 13. Bad flare 2008 but no health insurance so I dealt with it. Colonoscopy in July 2009 caused a perforated colon, emergency bowel resection. 2 fistula's, perianal and perivaginal.
Humira, probiotic, a multivitamin, calcium, magnesium, zinc, and fish oil. I also take Tramadol 50 mg and Klonopin (for anxiety) as needed.
Life may not be the party we hoped for, but while we are here we might as well dance!