What Is The Cause Of Vaginal Pain?

Hi i am a 15 year old female and I am having a lot of pain near my vagina and the area before my anus. The appearance is red, swollen, and raised slightly. It hurts to walk an especially sit. It does not hurt to use the bathroom but does hurt when i wipe. I dont believe there is any pus that can be squeezed out of it. I have tried some pain killers and applying heat to help the swelling but my attempts have lacked success. Please help!