Not sure this is great advice, but I did it with my 2nd. She was a projectile vomiter....& constantly hungry!
I opened the nipple a tiny bit with a hot pin & added rice to the formula. I'm sure others will not agree & it's not recommended bec of flow issues & allergies etc etc but when your frustrated you'll try anything...if it works!
For my third I couldn't get him to sleep! My mil told me how she used to swaddle her kids, stick them in a pram & leave them outside. In winter! In Canada! Lol. (She's British)
Well I did it for awhile...I didn't leave him! But the cold & a walk in the stroller helped him sleep longer for a nap...& I raked leaves or other outside stuff.

And my vomiter....I did gas meds for her & it didn't help. The dr said, "you just have a laundry problem!" As long as their gaining weight; that matters.

Hang in there!!! So wish I could actually help you out. Do u have a pump?