Campaign Problem

[xICooRsYIx]

So i just finished up the campaign on hardcore with my buddy. When the credits finished i was expecting all the achievements to pop up... but they didnt. So i went back to campaign, hit "select chapter" and it didnt give me credit for anything that i did earlier today. Some of the chapters arent even unlocked.

What the heck is that crap? doesnt this game have an auto-save? i mean i shut my xbox off when i had to go...but still thats why games have an auto-save feature.

Anyone else have this problem, or maybe know what happened?

-xICooRsYIx