Hey & welcome to GT!

Originally Posted by: dennissyracuse64If anyone has advice re: warmups or anything else that would keep me playing with joy and no pain, I would be most appreciative.

Yes, you should definitely make time to stretch & take care of your arms, hands & fingers! Also, try to play with as little tension as possible. Relax!

I have a tutorial on warm up stretches here.

https://www.guitartricks.com/tutorial.php?input=1525

Ask more if necessary & best of success with your guitar playing!