My iPhone 4 just randomly shut off and wont turn back on

Question

i was in class and got a text that i ignored. during the class, i got 2 or 3 more vibrations, notifications or new texts, i dont know.
once class was over, i decided to check my texts, however, my phone wouldn't turn on.
i tried holding the power button for a tad, thinking it might've shut off on its own, knowing it was pretty much full charge, maybe at about 91% battery life.
i know the phone shuts off at around 3% to conserve memory, and when this happens it shows you a red empty battery image when you try to turn it and then shuts off again. this did not happen so im pretty sure it's not the battery. i thought perhaps it had overheated so i waited a few hours. it's been around 9 hours, i don't think it overheated. i plugged it in the charger, that didnt do anything. i waited half an hour as i know when the battery is really low, it doesnt turn on right away when you plug it in. nothing happens i can't seem to get it to work. my computer doesn't recconize it either.
i have tried all combinations of buttons. i've held the power button, i've held the home button for 10 sec, i've held both, i tried putting it in DFU mode but NOTHING is working. im seriously panicking because i am no longer in warranty and it really ***** that it just broke like that while i was doing nothing...
if anyone can please help me get this baby running again, ill much appreciate it

Answer 1

Hold the Main Screen Button for a few seconds, then press the top button. My iPhone4s does this, I havent really found a solution on why it does this. But I found the solution to turn it back on, Holding the Main Screen Button for a few seconds then pressing the top button worked for me. If I find out why it does this and how to fix it, ill be back to repost.