I updated my iPod touch 4th generation from the latest iOS 4 update (i think maybe iOS 4.3.5 or something like that) to iOS 5.1.1 and my Photos, Videos, contacts, music, App data, etc. was deleted. How can I all the data back?

Question

I updated my iPod touch 4th generation from the latest iOS 4 update (i think maybe iOS 4.3.5 or something like that) to iOS 5.1.1. I updated to iOS 5.1.1 on a Windows XP Home Edition with the Service Pack 3 installed on the Windows XP (which I believe is the latest version). After updating, I unplugged my iPod from the computer. I saw that all my photos and videos were on my iPod, but there were no apps. A window popped up and told me to enter a passcode for my iPod. I entered a passcode. I then locked my iPod and entered what I thought to be the correct passcode, but my iPod remained unlocked. Desperate, I tried many passcodes with failure. After a while, my iPod became disabled for a long time. I decided to reset my iPod. After I reseted it, I chose to reset from my earlier back up. After reseting, my computer loaded on all my apps. But, when I started using my iPod, I realized all my photos, videos, music, app data (like game saves and high scores), etc. were gone! I have no idea what to do and I am very stressed about this! SOMEONE PLEASE HELP ME GET ALL MY STUFF BACK!!!!!!

Answer 1

Go to iTunea>Preferences>Devices and see if there is a backupright at the time you did the update. Then try restoring from that backup. If the apps are in your iTunes library, any app data will be restored to the iPod.
When restoring from an iOS 4 (or later) backup, if the device had a passcode set, iTunes will ask if you want to set a passcode (and remind you that you had protected your device with a passcode). iTunes will not ask you to set a passcode when restoring from iOS 3.x and prior backups.
Therefore, remembe the passcode that you enter this time.
It appears that if you restore from a backup, that backup is not subseqyently overwritten by the next backup.