Hi. A couple weeks ago I noticed what seemed like a raised bump (like a pimple with no head) on the left side of my scrotum. It was a little tender as a pimple might be. Now 1-2 weeks later, there’s a small cluster, and most of the bumps have black heads on them. If I scratch, the black heads come off and reveal open skin which then stings and becomes tender. Neosporin overnight has helped return to normal. It does not itch, is slightly red, and it is mostly painless (it’s sensitive to touch) unless disturbed. Any ideas? Thank you.