Good day, i went to visit my girlfriend 2 weeks back, we had unprotected sex but we both test. after few days i saw dry skin on my penis also under my foreskin but it's not itchy,have no pain no peeing problem. what could it be?

Penile dermatitis?: These symptoms are most suggestive of physical or chemical irritation, e.g. if a spermicide was used; or allergy to lubricant; or yeast infection (common in many women). STDs are possible, although these are not typical symptoms. But see a doctor or clinic if any doubt, epecially if symptoms continue a few more days. No sex until they clear up, then use condoms for a while.