When you start eating more carbs you will carry around more water weight because that extra glucose you'll carry around needs a lot of water molecules. So you need to be able to not freak out when you see yourself going up a few pounds. Once you've got that out of the way, anything else you gain is real and should raise an alarm. If you start adding more carbs you might need to pay more attention to your total calorie intake because you may end up eating more, driven by the ebbs and surges of insulin. Be careful, you don't want to undo all your effort!