One thing to consider is how you booked your airfare. You said you booked yourself and not through the cruise lines which could be a problem if the cruise is cancelled for whatever reason. I remember a few weeks ago when one of the ships (Century, I believe) was limping back to port and skipping all the scheduled stops, they were going to drydock the boat immediately for repairs. They cancelled the following cruises and offered those passengers a full credit on their cancelled cruise plus a 50% discount on a future cruise. HOWEVER, those passengers that booked their own air fare and bought non-refundable tickets were SOL. They could not get their money back for the air tickets and had to either use them to vacation in Florida anyway or lose.
BTW, I never ask anyone else what they paid for a cruise since usually no one pays the same price and someone usually ends up disappointed in what they paid. Be happy that you're happy with what you booked.