I have lower abdomen pain. painful when i press and after sex, sometimes i urinate blood after sex. feel nauseated all the time and have lower back pain?

These symptoms merit a careful gynecologic and urinary tract examination to determine the cause of the discomfort. Among the possible causes are infection of the pelvic organs and/or infection of the kidneys, bladder or urinary tract. It is an urgent matter which needs immediate attention. See your doctor or a gynecologist as soon as possible.