Not Able to breathe fully

[Jazz88]

I am 2 months post partum not able to breathe EKG, ECG, holter done all came back normal , Iron levels are normal only low on B12 , feel like my diaphragm is not working properly

I find that my stomach actually goes in when I inhale (rather than out) and out when I exhale.
It's worse when standing up and a lot easier when laying down, or stretching backwards.

Have you seen a pelvic health physio? Mine said I had a tight diaphragm as a result of pregnancy and then breastfeeding. She prescribed some deep breathing exercises which I did and it really helped.