I am a 20 year old male. Had unprotected vaginal sex a little over a week ago with a girl that I don't know that well, was intoxicated so only thought to confirm that she strictly takes birth control. About 2 or 3 days after, had a slight itchy red rash with tiny goose bump like bumps on penile shaft and about the size of a quarter and a little bit of redness at the base. lasted about 4 days at most and is now gone without ever blistering up or busting or being painful or anything. I also had a bit of redness on my scrotum, but that could have been more from poorly aimed itching in my sleep. there were no bumps or lesions or anything. Now I have a larger rash thats very similar and very itchy over between my left hip bone and pubic region, and a little bit in the middle right above my pubic region. The rashes are splotchy and some are kind of ovular, but theres also just sort of a couple that are more rod shaped. They have a relatively distinct border, but aren't like a dark red or anything. I also have a circular shape on the inside of my right elbow that has little bumps and is sort of pinkish. It looks about like the whelps i used to get from playing paintball, but the skin is only raised where there are tiny bumps, so i assume it's not ringworm. Is there any kind of STD that could be spreading like this and the only symptom be a mild rash and itchiness? I have yet to find a reliable explanation. I thought maybe scabies, but the pictures i have found look nothing like that I have. I also have never had many skin problems at all, and have had an allergy test that came up negative for all the basic things tested. I have also never been one to be sensitive to certain soaps or anything.