Can neuropathy have sudden onset? are there causes other than diabetes? 4 days ago i suddenly developed tingling and pain in the bottoms of my feet. can't see pcp till feb 18th. i do have lower back issues, can that cause it ? sorry 4 multi question?

Peripheral neuropathy from a toxicity or sudden nerve injury ( one nerve affected) could have a more abrupt onset but causes like diabetes,vitamin B12 deficiency, alcohol abuse have a more gradual onset.

Sure, such as neurotoxins, Guillain-Barre, etc. Regarding your feet, possibly small fiber diabetic neuropathy but see your doctor Doubt LBP is cause!