So you believe that December 21 2012 is your last day?

If you do believe this theory , your incorrect. On December 21st 2012 the only thing that will happen is that the Mayan Calendar will reset. That doesn't mean we all die, it just means that the Calendar will be renewed. And if your catholic, or christian or anything like that , Why would you believe this theory??!!
God determines if you shall make it to the next day. No human shall ever know when or how the Earth will end. That's because it's God's job to know