Excited Nervousness

So I have my first big Wedding to Photograph on the 21st.. I am super excited and blessed but also nervous beyond all belief.. I have a bigger SD card, extra AA batteries for my external flash, mini softbox for external flash but no spare battery pack for my camera :( I am not sure what to do.. I have been asking around for one but nothing.. I have a few friends and fellow photogs who have been giving me encouraging words and advice but I still have doubts that I can be as great as what people think I can be.. I am trying to keep my head up and not psych myself out but still.. Anyways that's really it for now.. just worried I will let everyone down and that is not what I want to do.. I want to photograph and edit photos that will make them proud for hiring me.. Please just keep me in your thoughts and prayers.. If I can't find a spare battery pack I am going to need them..