Milk can take 3 days to 1 week to come in. Before it does you make colostrum (liquid gold), there is not much but it is awesome for baby. If you are worried about milk supply, there are some ways to boost it, fenugreek greek, mother's milk tea, basil essential oil, fennel essential oil, and maxi milk are just a few. The book, 'so that's what they're for' is great as well. Good luck!