Need advice.

I stopped my birth control pills about three weeks ago due to cramps and my uterus feeling sore to the touch. I did not have a period on time but I know that's normal due to the birthcontrol. The soreness and cramping stopped for one week. Now its back and I have pain during sex and my stomach is tight, but rounder but no weight gain that my scale shows and it's sore. I can't lay on my back or stomach while sleeping due to it being real uncomfortable. My OB/GYN can't see me until may and every test I have taken has been negative. Help?