Hello, My Husband Randomly And Suddenly Got A Radiating Pain

Hello, my husband randomly and suddenly got a radiating pain in his lower left back (love handle area) to lower left abdomen. Before the pain started he lifted a heavy recliner chair. But it wasnt an instant shart pain, it started approximately 15 mins after. I ama nurse and first thought maybe strained back muscle, now i am thinking maybe kidney stone? He has never had this pain before.