I'm not strong enough

I had my baby girl on the 24th, at 12:36 am. I didn't know I could love anything so much. Tonight will be the second night at home without her. She's in the NICU and due to vomiting and not being able to keep her food down properly . They are running tests and don't really know what's wrong. They think maybe an obstruction, Maybe something else. The are taking what feels like forever to run tests and get any results. She could be there the next week, a month nobody knows yet. I'm just breaking down, I'm physically not strong enough to know there's something wrong with my baby. Everyone keeps telling me to not worry and think positive but I find it impossible. I keep thinking he worst, and it's taking a toll on me. Ive been on this app for 9months when I found out I was pregnant. I've seen all these wonderful stories and I just don't know why I'm not one of them. Anyone else going through something similar? I just want to know how to get through this. I need advice anything helps.