Sorry, dude. Pictures of private parts (or gross stuff) isn't allowed on here. There are people who are younger than 18 who regularly use this site.

Anyways, on to your question. If you're not having any weird discharge from your penis, I don't think it's an STI. It could be something heat/moisture related. Do you work out/play sports often? It could be a form of a heat rash.

However, if it persists, and, more importantly, if it makes you uncomfortable or if you feel any pain associated with it, I would highly recommend going to see a doctor. They can prescribe ointments or topical treatments to help. Until then, keep it dry and cool and see what happens.