dear Scot,
Twitching of a finger can have varied etiology.
Our body movements are been controlled by certain areas of the brain, which is governed by various chemicals called
neurotransmitters. Any change in the local or generalised levels of these chemicals in brain areas , can give rise to associated symptoms. Similarly, movement of little finger is governed by part of brain which involves a chemical "dopamine", essential for proper movements( smooth movements) of body. Variation in the levels of dopamine can lead to twitching of fingers, as experienced by you.
Now Parkinsonism is a disorder, which consist of generalised dysfunction and set of symptoms clinically, and need to be confirmed on investigations like
MRI,etc. It predominantly is due to depletion of this chemical of dopamine in brain.
Therefore, there is possibility of it being due to Parkinsonism, however it is difficult to confirm as I can't see any associated symptoms or no investigation done as yet.
I suggest you to follow the advice of your treating doctor.
I hope to have satisfied your query.
welcome for further information.
thank you. stay healthy.