Do you mean it's not starting up when you maintain both home and power buttons pressed down together?
Your phone might drained the battery itself?
What happens if you plug it into itunes?
Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_0 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A334 Safari/7534.48.3)
It is warm because of a physical fault, or more likely a software issue which we see a bit since iOS5.
Plug it into the wall charger and leave it 30minutes. When the battery is VERY flat you don't see anything on the screen for a while. Give it a while
After this press and hold the home and power buttons for 10 seconds - no less
how? is there something wrong with it?
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nothing happened.....
Anything happen before this happened. Was it dropped or were you putting in new software? Tell us about your phone.
Getting warm could be the CPU or there can be a hardware problem. If you can't get it restarted you got to get it replaced.
Mine shut off unexpectedly yesterday as well. Did the 10 second home and sleep button hold and it rebooted. No problems before or since. Wonder if it's a data bug that caused something. Odd.
Have you tried the power button? It's near the top of the phone.