Battery life sucks. What can I do?

I have a Nokia Lumia 920. (hold your laughter) and I already hate the phone. The only thing I liked about it was the battery life and the camera. Now my battery is dead in just a few hours maybe less. Even if I'm not using it. And it gets hot really quickly. And people are saying to take the back off and let the battery sit, but the back doesn't come off of a Lumia 920. I can't do a factory reset because I have over 1,000 photos and 2,000 songs and they can't be backed up on the phone. HOW DO I MAKE MY BATTERY GO BACK TO NORMAL?

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