Talk to General Physician on Lower Back Pain

I have lower back problem since 8th ramzan. it all started when I sat on bed for 5-7 hours constantly using laptop due to work from home, since then i can't sit or bend or wash face without pain. sitting on commode is also painful. can either lie on bed or stand. sitting is painful after 2-3 minutes. already ate medicines by doctors for many days. recently got kidney infection due to stone so now worried about eating any more medicines. kidney issue is ok now. please help for this lower back pain. I'm only 30 yrs old but my tail bone as well as lower back seems 70+ years old , pains a lot. :(