Stressed or Excited?

[ShannonSides]

When I let my hamster out of his cage to explore/play in a safe area, how do I tell if he is excited or stressed? I set him up with about four square feet of open space with a bunch of toys he is familiar with and place little food:treats throughout. He seems a little frantic/stressed when he starts, but after about ten minutes he seems to calm down (stops and grooms himself occasionally, shows interest in the toys and food, etc). How can I tell the difference between if he is excited or stressed?