Check for fuses - you might have blown one. Or this machine might have an over-amperage shutdown mechanism than needs to be reset. But a crash on one axis shouldn't have stopped them all; it sounds like some kind of safety switch must have been triggered. Or it might be that your machine requires homing before doing anything else, and disrupting a home switch made it so it couldn't keep going. Look to see what was supposed to happen on the side where the homing failed - is it a little tab that is supposed to go into a slot? Or a lever arm that's supposed to be depressed?