It could be several things. First of all, do you have any problems with urinary or fecal incontinence to see if it's a deeper issue with your back like a herniated disc? Did you have problems with your back before this? It could be shingles which is the chickenpox virus. It starts out with pain tingling in a specific area and then usually you break out in a painful rash. Shingles can happen due to a lowered immune system and from Covid. What I would do is go see your primary care Dr or an Urgent Care so they can review your symptoms, take your blood work.

This is not likely due to the virus alone. If it persists, call your doctor. A neuritis or nerve compression may be involved.