Thank you all for the input and thoughts.
I spent some time on the set up and discovered that someone (probably me) had really messed it up.
I made a lot of adjustments starting at what I use on everything and changing for comfort from there.
This morning I did another ride of about the same time and effort as previously, except for that I stretched my back before and after the ride.
Good news, back does NOT hurt!!! But my right knee does. I will tweak my shoes/pedals a little to try and alleviate that.