Pimple-sized masses in rectum

[inquisitive4]

In the shower yesterday I noticed about 4 pimple-sized 'masses' (not sure what word to use) on the wall of my rectum near the anus, and I am unsure whether I should be concerned. They are very small and are not painful. I am a healthy 21-year-old male and I have no pain passing stool, have had no change in my bowel movement, and have never bled while passing stool. I should mention that, last year I developed a hemorrhoid that I think has decreased in size. I haven't thought about it since roughly last year.

I am a bit of a hypochondriac, so my first conclusion is that I have cancer, or polyps, even though I am young and colorectal cancer does not run in my family. I feel like they might be enlarged blood vessels, given that the area is very sensitive, etc. Should I be worried?