Too much sex, hidden pain in the urine may be acute urinary tract infection, prostatitis, vaginitis, pelvic inflammatory disease, etc., should be timely consultation to identify the cause of the disease. 1. Acute urinary tract infection: mostly seen in women, after sex, the external genitalia did not wash clean, because the female urethra is short, straight, wide, easy to cause bacteria retrograde through the urethra, which leads to acute urethritis, sometimes there may be an acute cystitis, inflammation stimulation of the urethra and the bladder, which may result in frequent urination, painful urination and other symptoms. 2. Prostatitis: It is not common for men to experience frequent and painful urination after sex, but it is possible that after sex, due to the more obvious prostate congestion, and men themselves have chronic prostatitis, prostate congestion leads to the aggravation of chronic prostatitis, and the symptoms of frequent and painful urination that occur after sex. 3. Vaginitis, pelvic inflammatory disease: If a woman suffers from gynecological diseases, during sex may lead to germs invading the urethra, thus appearing the symptoms of hidden pain in urination. This symptom alone is not enough to diagnose the disease, the above phenomenon may also be caused by other factors. It is recommended that the patient go to a regular hospital in time, ask the doctor to clarify the cause of the disease, and give targeted treatment.