I am sorry you were so upset and scared after the nurses took your blood. You sound like me in that you need someone to tell you exactly why they were doing it and to reassure you that everything was going to be ok. Do you have cancer nurse you can call to talk with?
Chemo does get worse as you go along but once you are finished with it you will feel good again. I finished mine almost ten weeks ago now and have finished radiation 12 days ago. I can honestly say I find it difficult to remember how awful I felt after my chemo treatments. I had a three week break before starting radiation and by that third week I was feeling really good. Of course that was short lived because now I am recovering from radiation.
We can get through this and you are such a positive person so don't beat yourself up for having the odd day here and there where you fall apart. It is normal and to be expected.
Take care of yourself and ask lots of questions.
Big hugs
Joy xx