parkinsons is a funny disease in that a large number of people are atypical, me for example. i had no tremor for years and still have a reasonable sense of smell.
i think there is no evidence that coke causes pd or msa. self-blame is often an early behaviour but pointless.
if it is msa it may not be clear for several years. symmetrical symptoms are a sign of of p+, but only a sign not a certainty.