Cows milk protiens can be difficult for some people to digest, (was for my boys - consitpation in one & vomiting in the other) so honestly in my opinion if it is causing problems I'd hold off & offer more other dairy & plenty of water... yogurt & cheese are just as good if not better than cows milk.... my ds#2 has only just started drinking milk at 17mo, before that all his calcium came from bf, yogurt, cheese & green leafy veg... my Nurse said even if I stopped bf & he didn't drink milk that was fine as long as he got the fluid & calcium from other sources.