Sudden, severe pain in one testicle
Pain that starts quickly and may wake you from sleep
One testicle sitting higher than usual
One testicle lying at an odd angle
Swelling of the scrotum
Redness or darkening of the scrotum
Nausea or vomiting with testicle pain
Lower abdominal pain along with testicle pain
Tenderness or extreme sensitivity of the testicle
Pain that does not improve
A testicle that feels hard or firm
Symptoms after injury or without any clear cause
Immediate need for emergency medical care if these symptoms are present