On the hell of getting old

Having chased everyone else to bed in what is almost a sane hour, I am now sitting up because my bad knee has discovered a new way of playing sillybuggers. Instead of the usual "okay, you must shift it after having left it either straight or bent for N minutes, and there will be a sharp pop with a bit of pain as you move it to the other position", which I'm tolerably used to, we now have "hi, we are going to be dully uncomfortable building to unbearable--but with no actual pain--no matter what position it's in". Have taken ibuprofen and am elevating it in the hopes that this will do something or other. Am also wondering if falling on it Tuesday (I have a lovely skinned knee) had some effect, especially since that was how I injured it in the first place, but a) it seems a bit much in the lag time for that and b) should it not be then hurting in the fashion it did when I first committed mayhem on it?

At least I don't have to work tomorrow.