Q: since i updated ios6 my ipod when i connected to the computer frozed up and then it turns off/on and then white screen and then turn off/on and sometimes it does like if a tv doesnt have signal or watever it does that ... im scared of losing my ipod what

since i updated ios6 on my ipod directly from it it started all fine but then i pludget on the computer and it froze ... it only shows the apple it doesnt go even to lock screen have being like a day with 3 hrs since my ipod froze and sometimes shows a white screen.. i had tried to like turn off but cant its all time turn off/on what i have to do? please help me!