I have this burning like itching feeling in the top of my vagina. Like on the lips near the top is like cuts or a burn looking thing. I'm not sure if its a yeast infection or what. In the past month I've had unprected sex with 4 diferent guys. Should I be worried its an std? Also about a week or so before this my clit was really sore and hurt to even walk it was senitive. What could that have been?