I'm using greenp0ison, and an iPod 4th Generation on iOs 4.2.1. It finally came off the white screen, but its not jailbroken. Should I try again, or could it brick my iPod? if it bricked my iPod, I would like wanna kill myself.........

you CAN"T brick an ipod!!! all you have to do is restore it in itunes

if you are new to jailbreaking, just keep trying.
links for you-->>
http://modmyi.com/forums/iphone-news/748750-how-jailbreak-iphone-3gs-4-ipod-touch-3g-4g-ipad-greenpois0n-ios-4-2-1-a.html

http://www.iphonedownloadblog.com/2011/02/03/how-jailbreak-iphone-4-2-1-greenpois0n/

I succesfully jailbroke my iPod with red snow so I reccomend using that instead and you should put your iPod into DFU mode again...look up how to do that. Then re-jailbreak it with red snow.

im not answering at all but that happened to me and it just stopped doing the text halfway thru. and ive tried it like 10 times.....

Nothing you did is wrong! simply hold the home button and the sleep button until it restarts then try again:)