I also have sudden onset peripheral neuropathy, includes loss of smell.
-What were your glucose levels, did you get a urinanalysis?
-prozac seems to have a low incidence of Neuropathy, but the coincedence of the diagnosis of the diabetes, probably made you more vulnerable to PN.
Did your PN start before taking prozac?
from several accounts, PN CAUSED by diabetes takes years to accumulate, coming on so suddenly means: it can be anxiety related(temporary), autoimmune disease, drugs, infections.

How much of the vit you were taking?