I had chemo and rads at the same time, literally. I wore a pack with a pump and chemo in it, going through my port for the entire time of rads. I then continued with the chemo for a very long time.
Depending upon what meds they use and how your body reacts to treatment, there is no way of telling how you will feel. It is important, though, that you slow down during these procedures. If you're tired, rest, rest, rest.
A good friend will bail you out of jail...
but a true friend will be sitting
next to you saying,
"Dâmn... that was fun!".