Ipod Touch 5, IOS 6 wont turn on!

Okay... so today in the morning i was on instagram.. and i tried to update a picture.... but it just crashed or so went off... like it went to the black screen.. then i went to it again but this time i went to facebook and it did it again.. later on i put it my ipod on my pocket and when i tried to go to music it didn't .. it stayed on the black screen! and i've tried to hold both power and menu button at the same time and nothing happens !!! it's aweful! and it's driving me insane! help me , please. I don't know what to do, also...when you like.. tap on the back of the ipod, it makes a weird, sand sound like there's something loose. ALSO when i plug in onto the computer, it does not do anything, its like i didnt even plug it in, but my ipod gets super warm/hot in the back.