What Causes Tiny Clusters Of Bumps On Vagina?

Hi I am 18 years old and I am sexually active but I always use protection. A few days after having intercourse I noticed that I had tiny clusters of bumps on my vagina walls that look like heat bumps. They are really itchy and burn. To stop the burning I bought a Vagisil Cream and wipes and they seem to work but only for a certain amount of time. Do you have any idea what this is?