Sick Rooster??

[MelissaBA]

I'm not exactly sure what is going on with my little buff orpington rooster. He is about 7 weeks old. He sits around and closes his eyes as if he is sleeping and today I noticed him tucking his head under one of his wings. I have watched and he is still eating and drinking water. I have him with 10 other chickens his age and they all seem ok. This has been going on for a couple days. Does anyone have a clue what could be going on?

 

[MelissaBA]

When I say "he sits around" I am talking about he seems like he has no energy, doesn't move very much. I just recently moved these chicks from a brooder box to the outside and the past couple days our temps have been pretty cool. Could this have something to do with it?