Here is an update: Since Wednesday, I have been doing a lot of stretching, ice, Advil and mostly resting. Can't keep on the Advil long term as it upsets my stomach.
Today (Saturday): rode 57 miles, 4000 ft of climbing. Not hard, but decent pace. Wore a knee strap brace, drank 2 bottles of Perpetuem and one of Gatorade as it was 85º at the end.
Knee: perfect! No twinges or pains at all. I wish I knew what happened earlier, but I think I am back in business.
I'll continue with the stretching and thanks to all who offered advice. Ride On!