Brief Answer:
More likely essential tremor.

Detailed Answer:
Hello and welcome to "Ask a Doctor " service.

I have read your query.

Essential tremor typically begins in one hand or arm and with time may affect both upper extremities.

A certain degree of voluntary control also points towards essential tremor.

Essential tremor is considered to be a neurodegenerative disease, but its cause remains still unknown.

In some cases, tremor may be caused by other conditions such as thyroid dysfunction, electrolytes imbalance, etc.

Parkinson's, in the other hand, besides tremor, debuts with other symptoms such as decreased dexterity, facial expressions, autonomic disturbances, cognitive and depressive issues, gait problems, etc.

So, in your case, I would say that it's essential tremor the condition.

Hope you found the answer helpful.

Let me know if I can assist you further.

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