@SummerSloane CleanMyPC isn't an antivirus, and neither is Smart Game Booster. Still, I'd suggest trying to play with both of them disabled, particularly CleanMyPC. Apps like this can occasionally delete essential system files and often delete data you'd prefer to keep because it's flagged as redundant. (Imagine you made a backup copy of your favorite Sims 3 save only for the cleaner app to remove it for being a duplicate.)
I'd also test without mods, at least at first. If everything is normal, you can add back any NRaas mods you use and test again, then add back a few others if you have any and see what happens.