I'm pretty worried right now, the pimple I had on my penis shaft turned into a blister, now there's a dark spot in the center of it. I've never had any sexual contact with anyone though. What could it be? Please help.
See a doctor. It is not an std. You have to have sexual contact to get a SEXUALLY TRANSMITTED DISEASE. Pleas note the operative words are SEXUALLY TRANSMITTED. No sex = no std.