Did you hot tighten the nozzle while putting it back? Don’t think it caused your current failure, but cold tightening can lead to more clogs in the future.

I think layer shifts can be caused by many different things, but the first thing I’d check is that the bed carriage can move freely and there isn’t something mechanically blocking it, like a wire or a misplaced screwdriver. The second thing I’d check would be the belt and gears, so that the bed can’t move without the stepper motor also spinning.