--certainly, many drugs are neurotoxic (and Mrs. D can chime in better regarding your list), and alcohol can be both directly neurotoxic or can cause neuropathy through depletion of vital nutrients.

Given the sudden increase in symptom spread, however, I'd suspect that new toxic exposures (something tainted that you recently took?) might be more likely--and I'd really look into that B12 leel, which does not sound optimal to me (though I'm sure it was not flagged as it was within the reference range----burt many of us think those ranges are set too low in most places; in Japan and some parts of Europe the low end of the range starts at 500 or 550).