What could it be if you have tenderness on the left side of your pubic/groin area in a male?

Groin pain. Think of a hernia vs lymphadenopathy vs a varicocele. Should probably be evaluated by a urologist.
Hernia? Muscular? Both hernias and pulled muscles in the groin may cause pain in the area you are describing. In general, a hernia is associated with a lump as well. I recommend scheduling an appointment with a general surgeon.