If your baby is spitting up until you see clear liquid you need to get her in to see her Pediatrician. Was there a particular reason you changed formulas? Has she been running any fever? If she is not containing her intake she needs to be evaluated. She possibly is eating regular because she is hungry. Please make an appointment and let me know how everything is.

Hello,
try not to worry. To check if she is getting dehydrated check 2 things 1 is she acting normal like playing cooing amd such or does she just seem to want to sleep even when it is time to eat. Do you wake her to feed? 2 she has a soft spot on the top of her little head where the skull has not grown together or harden yet is the spot seems to be sunk in the get the to the hospital she needs fluids and if you can not get her to keep her milk down try straight water if that does not work get HER IN. Dehydration for babys is not a good thing go to the ER if you have to. Her spitting up could be as simple as the flap to her stomach could
be under mature and that can cause this. This flap is right at the top of the stomach. Very common it will mature in time you may have to feed her by a tube
but my daughter threw up and after a few weeks or so she stpped as the flap had maturesd.
But check that soft spot and if you are not sure it is better to be safe than sorry later.
let m know what happens I will be praying for you.
taykare