My iPhone 6 is stuck on the "Temperature" screen
Almost every time I use the Pandora application it heats up my iPhone 6 and drains the battery at about 1% a minute. This time I pulled it off the charger (attached to my desktop at work), closed out Pandora completely and turned my phone completely off so it could cool down. After it had cooled, I turned it back on and it went from the Apple logo to the "Temperature - iPhone needs to cool down before you can use it" screen. It has been 1 1/2 hours since I turned it off and it is still stuck on that screen.
Please, is there any way to fix this without losing everything? I don't back my phone up so I don't have any way to recover my things.
Thank you,