Hello, and thanks for your medical question on E Health Forum.
Based on the history, it seems that abdominal pain that radiates down to the lower back could be due to renal stones.
Pain that originates due to renal issues (Stones, infection) is episodic ,spasmodic or colicky in nature, originating in the flank and radiating to the lower belly, inner thigh or the testicles. It is associated with other symptoms like nausea, vomiting , etc.
You might consider consulting a Urologist for a physical examination and additional evaluations including a urinalysis, and this will help to initiate necessary treatment.
I hope you find this information useful.