Question on yeast infection or std?

One month ago I had unprotected sex for about two minutes. I wore spandex underwear, leggings and sweatpants to bed that night and did not urinate after sex. and took plan B the following morning. That same day I started to become itchy and inflamed in my vulva. For two days the itching and inflammation increased. I also had a white discharge that did not have a foul smell. I did not notice any sores, abnormal bumps or scabs upon examining myself multiple times that were not present before the unprotected sex. I also did not notice any flu like symptoms. I asked my partner if he had any std's and he informed me that he did not, although he may have lied or had not been aware of an infection. After three more days of mild itching I got my period. Once my period was half way through, the itching, inflammation, heavy discharge and redness stopped. Was this a yeast infection? No sores, over all itchiness on most of vulva, swelling of labia minora, no flu symptoms. Or could this have been a primary herpes outbreak? Inputs?