Hard to take deep breath

I just had a baby a little over a month ago. I was having chest and breathing problems after I had him that I got an ekg done because my chest hurt and I felt like I couldn’t breath.. they said everything was normal though and now everything feels fine. The only thing now is it’s hard to take a deep breath to feel satisfied or even finish a yawn. I can here and there sometimes but not all the time and since having him I feel like I constantly need to take a deep breath so maybe I take it more without needing to that I can’t finish it to feel satisfied? I don’t know. I’m not sure and Idk if I’m looking into it to much but anyone else have this?