My parrotlet might be sick.?

I was gone all day today and had asked my mom to watch my parrotlet. Once I got home I asked how he was and she admitted that she had kept him in his family room cage for an hour, then put him in the bed room cage away from interaction for about 8 hours with no contact!!! He was acting kind of sleepy and fluffy when I was leaving, and once I got home and took him out of his cage, he was still fluffed up wherever he walked. He ate a bunch of millet so I assume it's good that he's eating, but I'm afraid he is sick. I have had him for about 4 weeks and I have notices he has a kind of white line around his ceer and his beak gets sortof..... Dry looking. He drinks lots of water and is eating allot of food but is staying fluffed up when I hold him and when he is walking around. This is the first time I have noticed this behavior in him, oh and when he was eating, he was making this weird chirp that I have never heard him do before. Any one have any ideas as to what are wrong with him??? Thanks.