Z Calibration Fail  

Z Calibration Fail

I really hope someone here has something for me to try. I've had my MK2 for a year with nothing but great prints. But the last thing I tried to print was radically wrong, with a big x/y offset between two of the layers, and a resulting pile of spaghetti. I don't know if the print head caught on something (there seemed to be evidence of a corner not sticking), but somehow everything got misaligned. None of the belts seem loose and nothing seems out of alignment.

When I calibrate Z, or do Mesh Bed Leveling, the hot end jabs into the bed starting at point 6. I get "Sensor didnt trigger. Debris on nozzle? Waiting for reset" Of course, there isn't any debris in the nozzle; I've made sure of that)

If I run XYZ calibration I always get the message "XYZ calibration Failed. Consult the manual."

I ran and passed the self test, and the PINDA probe's red light can be made to go off by getting a piece of metal near to it.
When I auto home, the PINDA probe is within the circle, and it looks to be about a half mm or so above the height of the hot end. It seems to be in its in its holder securely.

I might glaze over at extreme tech jargon, but I'll shake it off and do my best to do what I'm advised. I love my printer and just want to get back to printing. Thanks, all.