Is my back ache coming from my kidneys or just plain lower back pain? what's the difference?

Colic defined: Colic is the kind of pain that grows in intensity. It may ease a little and then grow again. It's the kind of pain that the smooth muscle of the bile duct , or the ureter of the kidney causes . Most back pain is arthritic or from skeletal muscle pain. Sciatica is from nerve root irritation. The pain is different.

Pain character: Kidney pain (renal colic) is intense cramping. It tends to be right or left sided, depending on where the ureter (tube between kidney and bladder) is blocked by a passing stone. It shifts as the stone makes it way to the bladder (unless it gets stuck). Low back pain can also be crampy, but may be more diffuse. Consult your doctor or urgent care if there is blood in the urine.