I'm a gay male. A few days ago, I hooked up with a guy recently who didn't top me but he kept rubbing his hard dick around my anus and there's a chance that part of the tip went in at some point, but I'm not sure. It felt moist so I know there was plenty of pre-cum. Besides the anal play we only masturbated -- no oral sex. Now I'm particularly worried because I have a fever and sore throat. Should I be worried?