That is because your baby had too much of the foremilk (前奶). He needs more
of the hindmilk (后奶). Foremilk has a lot of water which is to quench the
baby's thirst. Hindmilk has all the nutrition he needs. Let your baby spend
as much time he needs on one breast before switching him to the other.
you can google "foremilk hindmilk". you can also google "baby poop green."
