if you want to buy it twice, just log out of your EA account at the bottom of the screen and then go through buying it again, this time using a different email addy. If the payment info is the same, that is fine.
Code isn't gone btw. Just make sure you're going through the link provided on the Facebook page and you shouldn't even have to enter the code, it should add to cart at $4.48. If you are having trouble with the code, you either are not doing that or you are attempting to redeem the code twice under the same EA account.