If you haven't already, you may want to take a look at this chart.
http://www.3fatchicks.com/forum/showthread.php?t=56861
This info isn't in the book, but it's a great guideline.
I followed the first week's plan from the first book pretty closely and then followed it in concept, but not as specifically the second week. We didn't experience the fatigue or "SB Flu" that you're referring to. You may want to make sure you're getting enough protein, good fats and lots and lots of good veggies. And since the beans aren't in the book and I wasn't connected to the good info here at 3FC, we weren't eating any of them in Phase 1.