Slight pain in left testical for 5 minuets and then goes comes back every few hours what could be wrong?

Intermittent torsion: You may have a phenomenon called intermittent torsion, where there is twisting of the testis cutting off the blood flow and then recovers. If this is frequent, get an exam by a urologist and he/she may get an ultrasound, but it may be difficult to diagnose. Otherwise, I suggest supportive underwear that can help stabilize the testis. Use antiinflammatories as needed.