Roborovski dwarf hamster help!!!?

Ok about a year ago i got this hamster and I named her Calliegh "DJ Stubby D" Duquesne, but we usually call her Stubby and she's a Roborovski Dwarf Hamster. Well anyways when Stubby's cage broke we got her a new one. It was bigger and there was a tube that was attached to it and if she crawled up there was a room that was attached to the lid of the cage and you could open that portion of the lid but she couldnt. And about 2 months ago maybe? She started going in there when she was awake and freak out! Literally! She would scratch at the sides of the "room" (it was as far as she could reach, she couldn't reach the lid) and she would do that for maybe 5 seconds and then move to another section of her "room" thing and do it again and only if you spoke loudly or tap on the lid she would stop and now she barley does it if ever. Was or is there something wrong with Stubby? or is this just a normal robo dwarf hamster thing? and here is a picture of her cage: http://www.pet-dog-cat-supply-store.com/shop/shop_image/product/70bd8541e6ca4f2c6c4e9ba872342fb4.jpg and im talking about the thing above the wheel and i just copied and pasted the link so tell we if it doesnt show the picture or something