The usual cause of front or back of knee pain is seat position too high or too low, right?

Well after last weekend's ride I seem to have both front AND back of knee pain. The pain is like the soft connective tissue (not sure tendon or ligament) is inflammed. It hurts behind when I bend my knee back and then in front when I lock the leg straight. The pain seems to be eased after gently walking a bit, but if i rest it a while it stiffens up so it hurts when i get moving again.

The ride was actually my best ride on this route. I seemed to be climbing more quickly and not getting out of breath as much. I felt great immediately after the ride; less tired no aches and pains for the first time. The inflammation crept in after resting for a couple of hours.

What can have caused this and how do i speed up the healing...move it more or less. Raise seat or lower.