my ipod touch 4g wont turn on???!!! plz help?

[Richard]

just rite now i was playing zombie cafe and i paused the game and pressed the sleep button. when i cam back, the ipod wouldnt trn on no matter wut i tried. its just a black screen. i tried to restore it but it wouldnt rk either. its not jailbroken, and this has happened beffore too. but the other time it came back on quickly. idk wut i should do i cant restore it or any thing, or atleast i think i cant PLZZZZ HELPP