What Causes Pain And Burning In Vagina After Having Sex?

I had sex about 3 days ago and it hurt kinda bad..Ever since it burns when i touch the lower right side and it burns if i move or if urine gets on it. I have a bump on the outside by where my thigh and 'area' meet but it's not bothering me too much, it just hurts like when i get raw from my underwear or pants. This has happened before around august and i thought i had a UTI so i took pills for it and got rid of it. It was worse last time to where it hurt real bad when i peed. It hurts when i pee now, but it doesnt hurt until right when im done. It's a burning and sore feeling. I have an appointment with my ob/gyn because i had a son ezxactly one year and a day ago but my appointment isn't until the 29th. Please help me Im scared and just want to know what it could possibly be.