My phone is taking pictures upside down

Have you tried soft reseting it. Holding the power and home screen buttons. For about 10 seconds. If not the next thing I would do is reset all settings.: Settings > General > Reset > Reset all settings. If that still does not work. Restoring to factory with iTunes and not loading a backup. Would be the next testing step. If still does not work. Then it would be something apple would need to fix for you. (1-800-MY-APPLE)

Get help with hardware features on your iPhone, iPad, and iPod touch - Apple Support

how are you holding your phone, is the home button on the right? If you hold it so the home button is on the left, your camera is essentially upside down.