How do I know if my hamster is pregnant?

[sillysally]

Hello my hamster is 9 weeks old Ive had her for a week now she is in a cage on her own. When I got her she was really friendly now she bites people won't let me hold her, she also drinks alot she eats it but stores loads in hyer bedding she keeps on changing her bedding around I dont know if shes still trying to settle in she also sleeps alot. But she is starting to get teets and yeaterday she seemed slimmer but shes a bit more wider around the hips HELP!!! luv Claire