Hi,
The lesion would heal spontaneously in a few days.
Keep the area clean and wear clothes washed in a few drops of chlorhexidine preferably and dried in the sun. Wear lose, comfortable clothes.
Apply calamine lotion and some over the counter antibacterial cream on the lesions.
You could take oral antihistamine or antiallergic medications for the itching.
Avoid sweat accumulation and any friction or trauma to the site.
Consult your doctor if the lesions still persist.
Post us if you have any doubts and update us about how you are doing.
Regards.
Masturbation is a natural way of exploring your own body, is nothing to be ashamed of, and cannot harm you. I wonder if you did it too hard, or more likely that some semen remained on the tip of your penis which then dried causing the irritation. Wash your hands before masturbation, be sufficiently gentle and wash your hands and penis afterwards. Use a gentle product in the shower or bath like Oiltum, E45, Eucerin or baby products. Do not share towels or flannels with anyone. Love loiloi x