i had unprotected sex last friday and now on monday i had a bump appear on my upper lip that flared up out of no where but then an hour or so later it went away then that same night i have something that looks like a cold sore on the corner of my lip then this morning thursday after i went to the bathroom i went to wipe myself and noticed i felt some pain with wiping i felt around and found a huge bump kind of like when a pimple begins to form. could this be some form of an std?