The first two or three days are a bit tough, you'll both be experiencing a carb withdrawal which can cause grumpiness and headache. Make sure you're drinking plenty of water - that should help a bit, and even though you might not want to look at any more protein you still need to make sure you're eating plenty. Keep things mixed up to prevent boredom.
It's a massive shock for the body, and you'll need a couple of days to adjust - stick with it, in a couple of days you'll wonder what was so difficult!