Well, Do not worry about the child if he is not eating. I know you are a mother and you are worried as I used to be when my child would not eat anything but drink milk only. Make sure you give him multi vitamin for the toddlar's I used from the Gerbar.
Yes, Nursing is good for the little babies but your son is two now , that means it is time for him to go. start giving him some regular milk in a sipy cup. He will love it becasue he do not have to work as hard in order to get milk. Also give him what he likes to eat even if it is only one or two things that he will eat for whole week. He is still a child and some kids eat way more less than the other but eventually they will start to eat.
Note: If you are giving him malt based drink such as horlicks, milo and others he will definatly would nto eat any food becasue that makes them full for a long time. So you might want to stop giving him such things.