So I just beat the game on realistic. First playthrough. And I didn't get the achievement for doing so. 
I looked at my scene select, and all of the levels have been beatin on realistic. 
I even restarted the last level on realistic. Beat that, and still nothing.
Has this happened to anyone else? 
Idea's on fixing it?

Sorry mate, this got posted in General Discussion. You're gunna have to make it again in the right forum so people know what you're talking about. It's a wierd bug but if you make very sure it'll get posted in the right place.

This was meant for Conviction. 
I don't know what happened.

Topic already exists Here.