JD750 wrote:
It seems by your urgency that you did not have a backup of the library. So you got luck, but now is your chance to put a backup system in place so if it happens for real, you will have a decisive course of action you can take.
Hard drives can fail. If your storing important information on a computer you really need to back it up. It's not hard nor very expensive. Of course if you don't care if you lose all your photos then don't bother.