I was inebriated last night, and made a series of very poor decisions. I ended up having unprotected sex with a fairly older woman. The next fact is fairly disgusting, but I feel honesty is imperative from a medical perspective. The next morning, there was a substantial amount of blood on the sheets. I can't imagine anything happened aside from her period starting while we were involved. I'm very anxious and paranoid that I may have received some form of STD, as likeliness of spreading increases during menstruation, let alone while unprotected. Is there anything I can do?