My cat just fell out the window...

Off food, unusual behavior (hiding, urinating, etc), "mopey" disposition, no desire to go out/roaming, difficulty in holding their heads up, overly "needy", overly floppy/malleable when being handled, slow response when pushing blood from gums, overly dry/wet nose, sunken eyes, splitting nails, disinterest in playing, ears not moving very much to stimulous, etc...

Sod the cat, I'm humped.