Babe, a lot of us have been there. The shock (looking back in retrospect, MY retrospect) is why it's not more obvious. You have had open abdominal surgery. Your have had a major life change. It sounds like you have a difficult infant. (I have had both easy and hard -- which is why I say it sounds like you've landed hard. Not your fault! It happens.) On top of all that, you are also being expected to maintain another life.
While I remember pumping, and am sure that's not helping, and can reassure you that you don't have to do it, it's the least of your problems now.
You need someone else helping, mother, nurse, whoever. Don't forget your husband is also new to this and however hard he's trying, is also not sure.
Above all you need to remember two things:
you have the right to more help. If your father-in-law had just open abdominal surgery, he would not be expected to be up and down physically, without sleep, breastfeeding. Don't blame yourself for not being able to do this. It's NOT YOUR FAULT.
it will get better. Even if your child is particularly difficult, it will. Try not to blame your child either. Some babies are harder than others, but ultimately it will be easier.
I speak as one who had three c-sections, two of them emergencies, and one of them a disabled child. Even he is easier at 19 than he was newborn, FFS!