It is weird, i know getting tested is the best way to figure this out, but i would like to have an idea of what i am dealing with before going in.

This normally only happens after i masturbate and only lasts a few days. I get redness around the rim of my penis head, yet there isnt like a cluster of bumps. It does NOT burn, hurt, and it doesnt look like ulcers.

After I go flaccid, It really isnt that red, but as soon as I get an erection it is there again, until a few days later. Any help?? Could it be just irratation?