1 week after having unprotected sex with a female, a lump appeared on the shaft of my penis, it is skin colours, about the size of a small pea. At first I thought the worst, I left it alone to begin with. After around a week the lump remained but it turned abit dark red, so I squeezed it and it popped, puss and blood came out, the lump reduced, but it is now back to how it was before, I’m unsure if this is a
STD or something worse