I think my dog is blind in one eye!?

My dog is 1 1/2 years old and i looked at her eye and it was a cloudy blue. She can sense everything around her, but i think she is using sense of smell and hearing. Also, today she was running into her crate when the door of it sort of closed halfway. she crashed into the side of the door. do u think that can be a cause of blindness? will it it go away over time? plz help!