My 22 y/o boyfriend notice a hard lump in his lower left abdomen sometimes painful somedays it larger&harder than others & somedays his testicald hurt?

Sounds like a hernia. Probably a hernia. Ok to see a primary care provider for an exam. No emergency is its not too painful, but should get it checked out. Timing of evaluation depends on length of time it has been there, and severity of symptoms. Hope this helps!
Hernia. Sounds like he may have a hernia. Please have him go see his doctor right away for an examination.