Is my hamster happy

[LaurensHaven]

Hi. I have a 16 month old Syrian hamster. She lives in a large zoo plus eco habitat with over 1000 square inches of floor space. She has lots of chew toys which I change up every now and then. She comes out everyday. And everyday I either sprinkle food around the cage or hide it or stuff it into toys. However she is still displaying stress behaviours. She keeps running round the edge of the cage and trying to climb the glass walls and her water bottle. I really don’t know what else I can do to make her happy and I hate to think she could be sad or stressed. Does anyone have any ideas as to what I could do? Or am I overreacting to this? Thank you.