My baby girl is 6 days old and she is drinking 4 oz every 4 hours I'm strictly pumping and supplementing with formula!! If she drinks a full 4oz of breast milk she is hungry again in 2-2.5 hours but if she gets 4oz formula she will wait 4 hrs I feel like this is a lot for a newborn!! She is not spitting up but I have had to keep uping how much I gave her bc she was acting like she was starving!! Is this normal