Small White Spots On The Left Lip Of My Vagina

two small white spots on the left lip of my vagina Good morning! About two weeks ago I had unprotected sex at a beach party with a guy I know for a while. At this beach there were some chemical toilets, the kind they use to events like this one, and I used it. Two days after my period came and because of the hot weather I was feeling uneasy and kind of itchy. Last night while showering I found two white spots on the left lip of my vagina and I noticed it is swollen. I've freaked out and don't know what might be. I should mention that I had a test about chlamydia, herpes and other diseases before that night and it came back clean. Also, I would like to say that months ago while in a steady relationship I was keep having various disturbances and infections. I've been through many examinations and analysis and all came back negative for diseases. I am very confused and tired of getting all these. I would really appreciate some help and advice!!