Hi I've got the Samsung Galaxy S4 and when I first got it everything was fine. Now for some reason my camera screen has flipped. Auto rotate is turned off so I don't know what's happened.
Do you mean that the images look upside down in the viewfinder, or that the pictures you take end up upside down? Have you changed the way you hold the phone when you take pictures? In some other threads I read about inverted camera shots, there was a mention that you have to make sure you're holding the camera with the home button on the right.
Might also be that the "Save as flipped" option is turned on. Open your Camera, tap Settings/General/Save as flipped, and make sure it isn't turned on.
Here's a link to the S4 manual. Refer to pp 86-87 for camera settings.