I've taken 12mg of xanax??

You'll be high and possibly not remember what happened while high. It's not permanent memory loss, but you will not remember being high if you take a lot. You should be more worried about how you will act while high. Xanax makes you not care about anything and act like a retard. I hope you're not around other people today or you will embarrass yourself. And if you drive a car you will crash it.

But what the hell, here in a few when in kicks in you won't care or remember anything I said so whatever.

You will quadruple the side effects already experienced by xanax

You should consult your doctor to be sure