What Causes Frequent Urination And Pressure In Uterus?

I am 36 and sexually active with one partner. For a week now I have had frequent urination and the sensation of urinating shortly after. The pressur and pain in more consistant and wakes me up at night. When I am having sex the intensity has increased as is easier to orgasm. I feel a throbbing and pressure on my uterus I have never felt before, even with UTI's in the past