Over the past two weeks my 13 week old has had less of an appetite. She weighed 9'10 on 10-24 and was the same height and weight last week (exactly 2 weeks later). Now suddenly my milk won't come in. She gets frustrated and won't suck long enough to get it down. When it does come in (while pumping) I can barely get an oz. She is obviously hungry and I think becoming dehydrated. What do I do? I know I can try to increase my supply but I've read that can take a few days. I'm afraid we need to give her formula or atleast water. This is not just a growth spurt. How long will it take to get more milk? Can she wait that long? I know my stress about it is only making things worse, but I'm worried she's not getting enough and I want to avoid formula.