I have severe pain in my lower back on the left hand side. In the kidney. If I sit still it stays at bay, but if I get up and exert myself or do some bending, I have severe pain. I feel like the nerves also went numb. when Im sitting down then the pai goes right across my lower back. Stays around my hip area tho. The pain becomes unbearable.
From your symptom you may suffer with left side para spinal muscle spasm, please take rest, muscle relaxant like thiocolchicoside and analgesic ointment and consult your physician if not improved with investigation like X-ray /MRI of LS spine for further treatment