Head shaking or tremors of the head are much more commonly associated with a condition known as BENIGN
ESSENTIAL TREMOR (BET) rather than PARKINSON'S DISEASE (PD) although some Parkinson's patients certainly do have elements of essential tremor present when the disease is advanced such as head and jaw tremoring....but in benign essential tremor head bobbing or shaking is a common finding. Blood tests are usually negative for any abnormality if the diagnosis is truly one of either BET or PD.
Good luck....it would be very pleasing to me to know that you will quit
smoking in this New Year since I can almost guarantee that as physically fit as you are at this time....I will nearly guarantee feeling ad being able to perform physically nearly 10x better if you would give up the cigarettes....not to mention how money you could donate extra if you'd like to your favorite charity! ;)
I very much doubt you are developing any symptoms consistent with a diagnosis of PD.
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