Lately baby isn't very interested in eating. He acts hungry every 2.5 hours but when I give him the bottle he just goofs around with it. He tries to hold it, knocks it down,he "chugs" then chokes, he bites the nipple(teething), then cries when we take it away or it's gone. It causes him to take in a lot of air, leading to plenty of burps, gas and spit up! It takes about 20 some minutes for him to even finish, if he does eat it. It's really frustrating in the middle of the night too. Generally he's been eating half the amount as before. I've been giving him puréed fruits or veggies at his morning feeding and night feeding. Anyone dealing with this? He's 5 months old.