So I just had sex with my boyfriend and for a period of time I was on top and I was mostly grinding opposed to bouncing up and down. I felt friction against my vulva but didn't think anything would happen. After, I went to pee and saw that my labia minora was huge! It is at least double the size and is very sore and warm to the touch. It also burned when I peed. So my question is, how do I get this to go away and how to prevent it in the future? (It's not an STI btw).