Hello all! I am struggling with my baby a bit in the bottle feeding department! I go back to work next week and he has to get this down! He is taking forever (almost an hour or so) to finish just 2 oz of milk and he is beginning to get frustrated with his feeding. We were doing so well for a the past two weeks. I'm wondering if I should switch his nipple flow from newborn (size 1) to the slow flow (size 2). He is 2 months old and we are using Phillips avent natural bottles. Thanks for the help!