It sounds like genital warts. They can appear anywhere round the genital area including the anus, even if you don't have anal sex. You need a proper diagnosis of course, but they can be treated at std clinics
I Have Wart-like Growth Structures At The Opening Of My Anus?
If I where you I would get it checked out but it might just be hemroyds if that's how you spell it?Try some preparation H if that helps and the bumps go down that's what it is.