3 weeks ago i had unprotected sex because the condom fell off inside of a girl who i did not know too well. 5 days ago i developed red bumps which were itchy. They are like raised red dots, about 3-4 of them in various places in the middle of the shaft of the penis. You can almost say they look like small blemishes without any pus in the middle, or an insect/mosquito bite.

I was so nervous and confused that yesterday i went to the urologist. He looked at my penis with a magnifying glass and some sort of purple light.
i was certain that i had an STD but then when he looked at it he said it was nothing but small rashes from irritation or possible yeast infection of some sort. He prescribed me nystantin cream and told me to take cortisone creme as well.

today, a day later I notice that the cortisone has helped on some of the bumps but a few of them are still present and more pink (prior to creme they were almost red/flesh colored dots). I think that even an additional tiny dot has appeared today. Again no blisters are present, and the doctor based on physical examination ruled out it could be herpes, warts, etc.

I'm so confused, i've never had any kind of red bumps or rashes. I will admit that I excessively masturbated for 1 week where I had a very sore penis prior to these symptoms developing. I'm wondering if i was too vulgar and self caused a a major skin rash? is that possible?

I will keep you all updated, i just truly hope a doctor with 30+ years of experience knows if something looks like an STD or not. Its so confusing for me, because i've never had red bumps on my penis shaft before.

thanks for any help, suggestions or advice, it's been a week of hell as i've not been able to sleep or focus.