When I forst got my Winter White Dwarf hamster,he would be really friendly and want to get out of the cage to play. Since I started giving him a food mix since he would only eat pellets ,he has drastically changed. I still give him the pellets but he barely consumes them.He is pretty lazy and all he does is pouch the food he likes (which would only be a few types of seeds) and then sleep most of the time. He acts like he's really frightened even though I have never done anything to him or taken him out of the cage if he didn't want to. I know hamsters are supposed to sleep all day but he would want to get out at least once a day to play. I still do everything the same and I treat him really nicely and give him lots of toys and entertainment. He's about 2 months old. He has highly changed and I don't know why. Is it the food mix? He is quite picky and doesn't eat too much. I give him fresh veggies and he eats most of them. What is happening?