I feel for you and know this pain. For two, 2019-21, I could barely walk due to nerve pain that started in my back and ran through like fire ants down my legs. Exhausting. Standing, sitting, lying, upside down, stretching, nothing offered relief. Comfort was gone. I lost the ability to touch my passion, fly fishing and camping in the high alpine. Couldn't trust my legs to cross a river, climb a hill, walk down a slope.
Eventually, it eased by returns every few months with a horrific bite, just to let me know that I am not in control. The last bout was a few weeks ago I wasn't sure I'd make it through without going mad. Every test taken. No root cause determined. Incredibly frustrating. All they can offer is pain killers and nerve suppressors. They turn my brain to mud but I take them when I needed because the pain is off the charts and unrelenting.
God Bless you and may you make a quick and lasting recovery.