iPhone 4S jailbroken iOS 5.1.1 HELP!

Hello. I was updating to 6.1 on my iPhone 4S earlier, and now I'm stuck in Recovery Mode. I updated the iOS from my phone (in Settings). Whenever I plugged it into my computer to finish the process, it comes up with Error(s) 21, 3004, or some other errors. I'd really like help, I don't care if I lose all of my data on my phone, I just want a stock iOS iPhone 4S.

Also, sorry if this isn't the place to post this, I just REALLY need help!