What could cause my Camera not to work in my Huawei Mate2

[Weaselbear]

My Hauwei Mate2 Camera does not work. I tap the Icon and the Camera comes as I am looking at the screen and it shows my Image on the screen for a few seconds then it turns it's self off and a message pops up that reads as such, "Unfortunately, Gallery has stopped." Also it will not turn to the Front Camera at All when I try to switch it. What could be Causing this to happen? Please Help! Thank You. Weaselbear