Newborn Formula Feeding Questions!

Hi all!

I’m a first time mom so learning as I go.

My son is 2 weeks old and for the first week and a half was on a 3 hour feed schedule eating incrementally anywhere from 2-2.75 oz each feeding. The last couple of days he’s been all over the map. One feeding he makes it to 3 hours and takes all 2.75 oz and the next he’ll go an hour and a half and take 2 oz. We just feed as we hear the “hungry cry” but not understanding why he was going 3 hours and now is averaging 1.5-2.5 hours.

The pediatrician changed him from Costco formula to Similac Pro-Sensitive due to him spitting up a lot. These SEEM to coincide but I wanted to see if any other mamas have any insight. We’re not getting any real break because if he wakes up from a nap he wants fed immediately no matter how long it’s been.

Any help or encouragement is appreciated!