Everything felt good today, I got to the gym this morning before work for some weights. The whole day, no pain - until I was walking to the car following work. I must have rested my leg wrong today while sitting at the desk, because my right knee is hurting. It has gotten worse as the night has gone on. I am not sure what it is, but will not be running tomorrow to make sure I don't irritate it at all.
Hopefully the nights rest and taking the day off will bring it back to normal.