2 week old constipated or trapped gas?

Bre

My 2 week old seems to have trapped gas or be constipated. He only pooped twice yesterday and not yet today i can feel him pushing and hear him grunting to get something out. He isn't crying in pain but his tummy is quite hard. He is exclusively breastfed. I'm waiting on a nurse to call me back. Anyone else's baby havinhg bad gas or something.