If you experience pain when passing urine, it could be caused by a urinary tract infection (UTI). Pain when passing urine can also be a sign of a sexually transmitted infection (STI). Symptoms of chlamydia and gonorrhea include pain in the penis when urinating, and also discharge from the penis and swollen testicles. Read below about penis pain, including causes, treatment options and remedies. Or get a personalized analysis of your penis pain from our A.I. health assistant.