I would be concerned. You are cutting it so close. Hopefully you can get through the airport. You didn't say if you are checking luggage. If so, you have to account for that time to retrieve it. Hopefully the shuttle is there on time. If you get through all that, hopefully there isn't any traffic. I don't know what Carnival's policy is if you booked through them, but the ship can and will leave without you if you miss the all aboard. It's always a good decision to fly in the day before the cruise.