The only thing I can consider could have happened is if you are on a hard drive that was in use at that moment. Obviously, any hard impact to electronics can be harmful.
I could be wrong here, but my understanding of current and the way a PC case is made, that assuming (for instance) that the ground in your electrical wall plug is correct, adding a quick shock to the case itself should not result in damage. I don't know about sustained current.
I would do a quick check of all connections, try to use iGPU if your computer is so equipped, check all the RAM is plugged in, etc.