I would suggest a skin biopsy to confirm/rule out small fiber neuropathy. This CANNOT be detected by nerve conduction studies and most with SFN have normal NCS.

You should also be worked up for diabetes (even pre-diabetes can cause neuropathy), and autoimmune disorders.

MrsD is the expert on B12, so maybe she will pipe in on your high level. Where you taking any supplements prior to it being tested? What was the level?