i activated this iphone 4s at christmas last year. today, i was in the car, parked, checked something on the phone (weather app, i am camping this weekend), got out, went to pick up my brother from school, tried to send him a text, but the phone would not leave the music app screen, no matter what button i pushed. i figured it was the cold weather, and decided to try to use it later. but when i looked later the screen was black, no response to any buttons, even plugging it into itunes didnt do anything. i have tried restoring it twice, to no prevail. and no, i did not putt it in DFU mode or go crazy hitting buttons, hitting each button at most 3 times. this phone is how i manage everything in my life, and it is crucial i get it working. any help?