Bob,
Just answering from my own experience, the first week of radiation there really weren't any bad side effects. However, chemo started the same time and I had a lot of nausea and vomiting from that, especially the first round before they started giving me Zofran, during the first week. So it wasn't an easy week. Some people have a much easier time with chemo, though.
I think the easiest week was the second week because I still only had relatively mild symptoms from radiation and the nausea from the chemo had mostly ended. By the third week, the mucositis started pretty badly, I needed more serious pain meds, and I also was fighting a urinary tract infection caused mostly by low white blood cells. From there on in it got worse, sorry to say.
Nelie