@sister I was like you, I came good about day 6 to only be knocked down, by the 5th week though I had no reprieve and it was back to back til the end, don't know why that was.
I didnt work with my Exercise Physiologist until I was well finished Chemo I was just too ill and she doesnt work with anyone in treatment generally as she said its time for me to heal awhile before we tackle it. I enjoyed working with her and it was a very long road to recovery as I had to learn to walk again. I have lost all muscle mass thanks to chemo so even at 2.5yrs post have a way to go to reclaim that and also to shed 8kg. I am however finally back working full time and requires alot of energy, so really happy how Im managing it all. The fatigue does get better, but be careful exercising as my EP said it can do the opposite and set you back if you go too hard and dont pace yourself.