It should fix it. Testingcheats can make your game go a little or a lot crazy. Just remember next time once you get done using it to just turn it off again.
However, I have not heard of it actually causing your game to freeze up. It could be an entirely different problem like bad CC (which we can't really help you here with), or if you have a lot of extra objects lagging down the speed (like water fountains, gnomes, or anything that works randomly without any help on your part).
I would try making a copy and hopefully that will help!