Reflux (or GERD) is when the valve that closes off the top of the stomach comes open after eating. It causes formula to move upward into the esophagus. Stomach acid burns the esophagus. My son initially had the silent reflux where they don't actually throw up the stomach contents but it moves up and down the esophagus. Because that valve is open when it should not be, it allows excess air into the stomach causing the painful gas. Reflux is worst when lying down flat which may explain why she cannot sleep very well. Try letting her sleep in the carseat, swing or bouncy seat.
She also may not be tolerating her formula very well. You may need to switch to another. You can give her gas drops in every bottle, that will help with the gas. It also helps to make the formula ahead of time and just warm it up. When you shake it up to mix it, it causes alot of air bubbles.
Mama to Ethan