My son is 1 year old ... who eats food essentially ... has been consuming less food for these 3 days ... is giving cow's milk .... after drinking milk for 3 days in the evening he is vomiting .... no problem when drinking milk during the day ... he vomit only when he drink milk in the evening ... On the third day, when he go to toilet , it smells bad .... It's not like normal ....what happend to my son?