Stopped latching

Brittany • May 16th with first boy
My son is 3 days old, and initially did great with breast feeding. Even the consultants at the hospital Sao she was nursing great. This morning before we left the hospital he gave me some trouble, just started pushing off of me and almost like he can't suck. She came in and pushed on my breasts and he went to town. We got home today, I got one 10 minute feeding in around 4:00 so I tried again in 3 hours. He was not having it. So mad every time I tried. So I decided to pump some (have been doing this on and off) and feed it to him from a syringe. Problem is, 1. I don't know if he is getting enough food importantly. 2. Why would he just stop be able to latch? It's like he forgot how to suck or something. He just gets my nipple in his mouth and isn't sure what to do with it until he gets mad. We've even tried expressing some milk first. I am so exhausted and am just really needing some answers. My husband and I are getting frustrated with each other because we just want to feed our little man and make him happy but it's so stressful. I knew this would be hard but never expected this hard!