Jokeyman, thanks so much! Wonderful information, much appreciated. Yes, I've been watching lots of videos of pianists, observing their sitting position, elbow height in relation to keyboard, hand & wrist motions. So playing piano is not like typing, where the fingers act like little pistons pressing on keys. I can hardly wait to work in person with a teacher to smooth out the physical mistakes.
Lest anyone think I'm a frail granny, I'm a long time cyclist, work out regularly with a kettlebell trainer, take spin classes, & can still do push ups. I knew there were a few aches in the hands lately, but was shocked how diving into learning piano set fingers, hands, wrists, elbows aflame. Mashing down on the keys several hours a day, no matter how much fun, taught me a lesson.
Thank you again, Jokeyman, for your insights.