[Takahashi]

I've had my girl since Thursday and I've noticed that the water bottle that I have (just a basic bottle that hangs with the metal ball in it, which is what she was using at the pet shop) still has the same water level in it and I haven't seen her use it, however she does grab at the metal part and bite it, it kinda looks like she's trying to figure out how to use it or she's struggling because nothing is coming out, but when I test it with my finger, water comes out. So, I put a wet sponge in with her and she hasn't touched it, I've also tried to give her water myself and she didn't accept it.
Now, this is my first time having a hamster and I've always had bigger small animals, so is she drinking, but she's so small that I'm just not noticing anything gone because I'm used to having bigger animals that drink more?
I don't want her to get sick from not drinking enough.
Any help would be appreciated. Thanks!