I have had unprotected sex with my girlfriend during her cycle of ovulation, and upon ejaculating I felt a jolt of pain in my urethra. It has been about 12 hours since then, and every time I attempt to urinate, the pain is overwhelming, and I am unable to pee. My girlfriend is safe, and has no STD's. I am wondering if I may have a urinary tract infection. What can I take to cure this? What can I do to ease the pain?