I have something similar. Near the head of my penis I have a red mark that is not painful , itchy or sensitive. The skin gets dry and flakes off, but the irritation is still present. It seems to be fading. I'm planning on getting and STD test, but I doubt its an infection. I'm at a loss, and that somehow makes it more disconcerting.
I don't think this is an STD--it certainly doesn't sound like one. Irritation sounds much more likely to me. I understand why you're anxious, but I think what you ought to do is wait till you see a doctor and leave the spot alone till then. If it's still there--it may have gone away by then--you can find out and be tested.
Best.
Dr. Rockoff
You worry for nothing. doesn't sound like a STD to me at all. It is very common to have bumps, redness on the penis. Most of the time it is from friction. Put some mosturizer on it.