swollen penis head

I am 26yo gay man with an uncircumcised penis.
I have a swelling on my penis head, on the lower part/circular thick part of the mushroom. It is not a continuous one. I had an irritation for 2-3 days in my penis when I had it for the first time and the lower part of the mushroom turned purplish and also every time when I rolled my foreskin back I had this irritation. I applied coconut oil over and it went off. ( also 3 days before this happened I took a leak in a very nasty and unhygienic place when I was out on a tour, because I had no other place to go pee, this was like 20 days ago)
Will this be due to any STD/HIV infection ?........................................(1)

And again from today am developing a small irritation on my penis head with very very few and tiny red dots like blood spots in the same part but no purplish shade or irritation/burning like earlier. I rubbed on it today to check if anything serious is happening like the previous time.
will this cause due to abrasion also ?................................................(2)

kindly write in your comments. thank you!!