I had protected sex almost a week ago and immediately after my vagina swelled up, which has happened before. But their is still some slight swelling present as well as very uncomfortable itching and something like a whitish type substance on my labia and around that area that makes my vagina looked slightly discolored in those areas. Today I also had a thick discharge but it was only about 1/8 a teaspoon, otherwise the discharge has been normal. There is no odor anything like that. Could this be a yeast infection, std, or is my vagina irritated from the sexual activity? thank you.