not getting enough to eat!?

Hannah • Hey my name is Hannah. I am a 27 yo SAHM 💙👶🏻 💙4/29/16 💙👶🏻 💙4/23/18
My son is 10 months old. Until fairly recently he was EBF and has a hard time the bottle. Well he is now in day care part time because I have gone back to work. His first week was last week. He came home on Thursday with very flushed cheeks and was very lethargic. He had no fever and wasn't complaining. I breastfed him and he was fairly lethargic for the rest of the day until after dinner. Then again Friday he came home with flushed cheeks. They told me that he is taking his bottles and eating as normal. This past weekend his usual wet diaper count has been down. When I pump at work I get 2oz per breast when I used to get 4oz. Is it possible my milk is drying up? I still feel a strong let down when he feeds and he is still drinkingfor the same amount of time. Any suggestions? Also he eats 3 meals a day and drinks water at each meal.