I think the sensors for compass, gyro and the accelerometer have failed. Then It looks like the Bluetooth, wifi, portrait orientation are also no longer working. Let me know if you facing above problems too. You definitely are going to want to get that phone in for service. Based on that there’s a few different parts on the phone that appear to be malfunctioning.

Same problem facing after I dropped my iPhone 5. I saw power button permanently pressed what should I do? ~Jiten