It's not an STD - I've never had an STD, and I just got tested again too. The symptoms are just like a yeast infection. Not much itching, just a lot of white/yellowish curdy discharge. A while ago a doctor tested my pH and said I had something like yeast only a different bacteria - when the pH goes "the other way" as she said. She prescribed these Antibiotics that made me vomit withing two days, so I couldn't take them. Either way, I hate Antibiotics and it didn't seem like the right thing to do. She did say that sperm is acidic, so sex can make it worse.