I have a pain in my left testicle and leftside

Patient: I have a pain in my left testicle and leftside of groin. I was afraid it might have been testicular torsion, but I have no swelling or discoloration in my testicles and scrotum. My left testical feels as if it is bruised along with my groin. But there are no lumps or indication of bruising or infection. The pain started last night, then went away and came back during work today. I am a truck driver in the oilfield. Some lifting is done every so often. What do you think it might be? Why does my groin&left testicle feel sore?

Symptoms: Pain in left testicle and left side groin area

Doctor: