Feel like a failure (breast feeding)

My daughter was born 5 days ago and was not feeding properly, nurse suggest I pump especially because she became extremely congested so when she’d latch she couldn’t breathe… anyways, I was hand expressing first and would get 7ml.. I would pump in between and nothing absolutely NOTHING comes out. I had ONE good pump from my right boob and that was it.. I have no idea what I’m doing wrong.. when I hand express I get milk but pumping just isn’t working for me. I can’t stop crying because I want to breastfeed my daughter, even if it’s by pumping.. does anyone have any suggestions please? I feel like my supppy is going down because of this