Warts are contracted by direct rubbing against some one who has them in the genital area so they are most common on the penis shaft or pubic monds area and rubbing testicles on someones genital area would be painful as you can imagine.
Its most likey an inflamed hair folical as wrong area for a wart
Hi what your mentioning is not suggestive of any std and masturbation is zero risk. It would appear you anxiety is causing you to notice things that may have been there all along.
When i get genital itching i use 1% cortizone cream with aloe and itching clears up in a day but if your concerned have a doc check you out.
I forgot to say my only sexual exposure in the past two years (after full std check/all negative) has been mutual masturbation. No oral, no penetrative sex. I'm gay, by the way.