Failure to lift with the knees

Monday's failure to lift with the knees turned into a week long failure of almost everything else even remotely physical. While deconstructing the old bed frame I lifted a sizable & relatively heavy piece of plywood at a very odd angle, in which I didn't use my knees. Well .... didn't feel anything at the time, but later that day, a sharp twinge in the back that dropped me to my knees. Sigh, it was all downhill from there. A full week with virtually no physical activity except for constant stretching .... can't wait until Shinka tomorrow, its gonna hurt but I don't care. Solution to failures of this week .... lift with the knees, and stop getting old.