swollen labia after foreplay

Most times after foreplay my right side of my labia swells up and tends to stay that way any where from 1-8 hours. It hurts when i put pressure on it and sometimes stings when I urinate...After a few hours then it goes away and doesn't happen again until the next time im involved with foreplay, once i happened after i had sex but I am not sure what is wrong?! -

You could have really sensitive skin there, make sure your partner is washing their hands before any forplay to prevent any bacteria, and maybe you two should try doing it with a lighter pressure. If that doesnt help, check with your doctor... good luck!