I am a 16 year old male, and today when I was in the shower, I felt a bump right by the opening of my rectum. When I got out of the shower, I couldn't feel it anymore because it had gone back into my rectum (it's about 1/4 of an inch in). It's bluish and about the size of a pea. It is NOT sore, and I haven't noticed anything unusual with my stool, or anything unusual at all for that matter. I'm extremely nervous and worried about this, any ideas?