Suggest Treatment For Small Bumps On The Buttocks

I've noticed like for the past week, bumps near the hole of my butt, but on the skin. They're like little white bumps, and when I touch them, they almost roll and peel off. I'm not sure what it is. After I peel it off it bleeds a little. It's scaring me. I've only had sex with one person and he's only had sex with me. Is it herpes? What is it??