Suggest Remedy For Red Swollen Spots On Vagina

I have a red/swollen spot with a white head on the top of my vagina, puss comes out when squezed, however it wont burst, I had unprotected sex over 5 years ago, but since then just with my husband. I am also 8 months pregnant, it has just risen up over the last couple of days, is this just a spot and if so how can i get rid of it?