Hey ladies I've been breast feeding for 2 weeks now since my little one was born but as of Monday…

Hey ladies I've been breast feeding for 2 weeks now since my little one was born but as of Monday she refuses to latch or use anything but a bottle which I assume is because that's what she had at the NICU. She screams beyond anything I've ever heard from her if I even try so I've started pumping and bottle feeding it to her. My problem is that she eats so much and so constant that I cannot keep up with pumping and feeding. My milk has even decreased. I've had to start supplementing with formula in between feedings. My question is. Would it be bad to just convert to formula little by little? I feel so guilty but I just can't get enough for her and every time I pump it's after she falls asleep and by the time I'm done she is hungry again 😣 she only stays asleep longer with the formula.