Doctors said what I had was called "Guyon's Canal Syndrome" similar to Carpal Tunnel Syndrome but a different nerve. Doc said in many cases requires surgery to fix. I have no medical insurance so hope was low. Eventually feeling started to return and now feeling has completely returned.
My suggestion is that you consult a different MD if it acts up again.
Yeah, it sounds like a nerve problem but it might be something as simple as a bulging disc in you neck putting pressure on the brachial nerve causing weirdness down to your ulnar nerve which flows out to your ring and pinky finger.
That's what my adventure was.
What initially aggravated the disc in my neck was probably the prescription in my bifocal glasses. A too old of a prescription made me subconsciously hold my head at a weird angle.
Once I got my vision Rx corrected the nerve specialist I consulted gave me some prednisone and sent me to a physical therapist who gave me exercises to strengthen my neck and upper back to get things back to normal.
I have made those exercises part of my religion.
To this day I can't sleep on my back without my ring and pinky fingers going numb unless I support my head with a special support thing that that holds my head in traction. I bought that off the internet for about $15.
The rest of you, short fingers? Perhaps. If we're comparing pinky fingers I imagine I'm in the running for having one of the shortest here. At 5'1" I have the tiny hands of a moon goddess. My other instrument is the fiddle and for the longest time I considered getting a smaller (7/8) size fiddle. Then shorter than me fiddlers pointed out to me that its not so much the length of ones' fingers as it is the position one holds their whole hand in relationship to the instrument.
That plus you need to build up strength in you pinky finger.
Which brings my long winded explanation to something for
even those here with long pinky fingers to consider.
Many of us have the muscles that move both the pinky finger and the ring finger connected to the same tendon. Not everyone has that.
That doesn't mean that those who have that will never be able to move those two fingers independent of each other.
That only means we probably will need more dedicated practice to move them independent of each other.
Like Roxhum said, "practice, practice, practice."