Does this game have a weird FOV? I've had to stop playing it. I'm getting terrible dizzy spells everytime I turn. In under 10 minutes. It's horrid. Yet with hardly any action I'm getting this just walking about. Yet Battlefield 3 gives me no issues, nor does the Uncharted games.
This is worse than reading in a car.
Have you tried changing the FOV in your INI settings? Have a read of the first post in the mods thread