As I was creating my baby registry today, it dawned on me that I have NO CLUE what I'm doing! It began with adding bottles to the registry-idk how many bottles I need! I mean she can only use one at a time, what do I do with the rest? Fill them all up & wait? What size bottles do newborns use & when do I switch to a bigger size? I'm going to breastfeed and pump so should I only register for the bottles that go with the breast pump??