I feel like my toddler would rather be at daycare???!!! Help please!?

My son just started a new daycare this week and he loves it. He is 21 months old and a very happy baby. When I drop him off at daycare he is sad/pouty lip, but does not seem traumatized. I have checked on him on and off everyday to see how he is adjusting, everytime I peek in he is playing and running around. When my husband and I pick him up he is very excited to see us, but everyday an hour or so after we pick him up he is soo very bad. He will scream at us and throw stuff if we wont give him juice. I know at daycare they do not give juice and he is not allowed to walk around with a sippy cup whenever he wants. Which at home before we allowed this. I feel like when he gets home he would rather be at daycare. He somewhat seems like he is over stimulated and he has to calm down some. We try to talk and play with him but he will just scream at us. Anyone have any advice..? I feel like he is mad at us for picking him up ...I just want my sweet baby back :) Also at daycare they say he is doing wonderful...never has to sit in the thinking chair for being bad or never crys...??!