Trying to pump but nothing comes out?

Gave birth the other day at 37 weeks and 5 days. Labor was hard and it ended in me getting stitches, her being sent to the NICU for her breathing, and me not being able to see my baby for almost 48 hrs. Now I know my milk is either coming in or it has cause my breasts feel full and a lot heavier. She's having trouble eating and I have every intention on breastfeeding but nothings coming out. I tried to get her to latch on when I visited but she suckled and fell asleep after a minute. I'm trying to pump at home hoping she drinks my milk and gets better but nothing's coming out. I'm getting frustrated and sad. I just want her to come home. What do I do?