What Causes Skin Tag At The Anus?

For years and years I thought this thing I have was a normal part of my body, until recently when my boyfriend noticed it and said it wasn't. Ive looked up a lot of information and read alot of books but I cannot find out what it is. I now Believe it to be an internal hemorrhoid but it doesn't itch, burn or bleed and its always been the same size. I noticed it years ago after I had defecated and stood up something didn't feel right, when I checked it felt like a worm was protruding slightly from my anus. When I touched it or lightly squeezed it nothing happened (no movement so I figured it wasn't a worm) and after a bit it settled back up inside me and I wasn't bothered by it anymore. At one time I did squeeze it very hard, it popped and afterwards I felt very sick, after it healed I decided to just leave it alone. Can anyone tell me what the worm like piece of flesh is? Could it still be a hemorrhoid?
sincerely, confused and embarrassed