Camera's forward lens not working.

The phone's forward lens is not working. I turn on the camera, and all I can get to work is the selfie lens. I can't get the phone to use the camera lens on the back of the phone for forward pictures. The icon that normally is available to switch between forward & selfie lens, doesn't even appear on the screen - or I must have just gone blind. It might be a coincidence, but my flashlight / the camera's flash isn't working at the moment either; the camera's flash icon doesn't appear on the screen either.Any ideas on what has happened or how I can fix my issues would be greatly appreciated.  

Thanks