A.M. Got that completely right. A recent auto update from Micro$oft, messed a lot of keyboard settings up. Take a look at you "language settings" in the control panel.
Sometimes when I press 'shift' and 2, it creates an @ when it's meant to be a ". when I try to do an @, it creates a "! Why?
Your keyboard would currently be in the language of English [UK] instead of English [US].