What Do Swollen Vagina And Increased Urination Urge Suggest?

For about four years now, every once in awhile but becoming more frequent, I have had the uncomfortable sensation of feeling like i need to urinate constantly. Usually nothing actually comes out, yet I continue to feel like I need to go to the bathroom. I feel my g-spot/front inner vagina swollen into a hard knot and it feels like I m on the brink of orgasm all the time; the intense pressure is there and very, VERY uncomfortable. I have been to a doctor when this occurs and they have tested for UTIs. The test came back negative and I was sent home with a deal with it attitude . It s 4 am and I ve been woken once again with the need to urinate, but like usual, nothing happens. It keeps me awake at night and keeps me running to the bathroom all day maybe even in 5 minute intervals. These periods of time come and go lasting anywhere from one day to two weeks. It has very deeply effected my life and I can t just deal with it any more. Please help me!