Hamster
 

My hamster's fur is wet.
I'm not sure if is from her drinking bottle or is she sweating?
Should I put a fan for her?

well they do lick themselves to groom. i dont believe they sweat like that.

Hamsters sweat out the pads of their feet. Either your hamster has a grooming obsession or it's been playing in the water. Although hamsters were originally desert animals the domesticated hamsters of today don't always handle heat that well. A fan to help take the edge off can help out alot.