saves&tray disappeared, mods not appearing in game

@chalaaa03  Then I'm sorry, but it sounds like your content is gone for good.

I know it doesn't help now, but this is why it's so important to make frequent backups of your saves or anything else you'd be upset to lose.  (And that goes for data in general, not only Sims 4 content.)  You never know when a computer issue will wipe your data, or at least some of it, and backups mean you'll never be in danger of losing everything.