No, it's not normal to put on that much weight from treat or cheat meal. Apparently, your "treat" meal is too large or you're eating all the wrong things. While a treat or "cheat" meal is sometimes, recommended or some people say it's okay, if you have to fight all week long to get rid of the weight you gain from it, you have to ask yourself if it's really worth it.
Personally, I don't think a treat meal, every week is a good thing.