If you have it in your budget, but her something small to open on Christmas, and THEN tell her that her real gift is on the way from overseas. It will make you look like a thoughtful guy to be sure that she has a gift to open ON Christmas.
Next year, buy local, order WAY in advance, or pay for the 2-3 day shipping. Christmas comes the same day every year, so to be late with a gift is in bad form, and a lot of girls will outwardly tell you it is okay, but believe me when I say they won't forget you were late.
Relax... I'll need some information first. Just the basic facts - can you show me where it hurts?