Hi Michelle,
I forgot all about the anemia! It can be caused by either the chemo and/or the radiation. The blood flowing through the carotid artery gets zapped during radiation. The body replaces the red blood cells at 128 day intervals (I think it's 128 days). I also took a lot of megadoses of Diflucan for thrush which is a suppressor of white cells. I had low white and red cell counts. It wasn't quite bad enough to require a transfusion or Procrit. The anemia will zap your energy also. If the thyroid took a major hit, that can cause problems also. They usually wait a while after Tx to do a thyroid test.

Another obvious thing is eating. It's just like your car running out of gas. You need to eat to provide the fuel. Digestion can be impacted by chemotherapy and this can also be a factor.