Around last teusday I noticed a tiny red sore on the bottom of my penis head it did looklike it was a little open and a perfectly clear fluid was in the creices of it, i think they were white blood cells, but anyway after a few days it closed up and turned into this little zit thing. I have very sensitie skin and lately ive been wearing looser boxers and the head of my junk has been kinda scraping. Could this maybe be an allergic reaction or an infection? the last time i had unprotected sex was about 4 or 5 months ago. this is the first time anything like this has showed up. please help?