Marcie, congratulations. This must truly be a trip of a lifetime. I cannot imagine cruising for so long, 7 days being my current longest. You must be so excited!
For me, the biggest challenge would be fitting into the same formal outfits at the *end* of the trip! But I guess on such a long trip, you would have to get into a rhythm of moderation--a little less rich food, a little more exercise? It's certainly a long time to "party" and have no daily routine.
Have a great time.