My save has changed completely

This morning, when I opened the save I'm currently playing with, I randomly got a lot of achievements I absolutely did not get, all my sims' abilities were gone, they were unemployed, and they all had just one personality trait that was not what I chose for them. Also, the moment I started playing, they all got older. I already tried to repair the game, but it didn't work, and now I don't know what to do. I've really put a lot of effort into this save, and I don't want to lose it all. Any suggestions?