he (5 weeks) went 2 days with no poo but lots of wee, then this morning had a tiny green poo in his nappy, it was really dry and had stuck to his bumcheeks! i was told too much foremilk could be responsible - how do i remedy this? do you think i'm swapping boobs too soon? i have reduced the formula by quite a lot the last few days as well - could that be linked?