I had unprotected sex two weeks ago. I have had no symptoms except today i noticed some irritation in the groin fold area to the side of my scrotum. i wiped it vigorously with a wet towel after a shower and thats when i noticed the irritation. it is not itchy, no rash, I have no discharge, no pain, no burning during urination, no sores or anything else on my penis. Should i be worried or am i just being paranoid? I am slightly overweight and that area is typically moist and I had have chafing before. there are also several stretch marks located in the exact location. 40 yrs old, help?