That is not even close to enough time. Your best bet is to book a flight at or after 12:00 Noon if possible. Cutting the time frame a little bit closer is possible with FLL being so close to the pier but I wouldn't do it. Even if you purchase travel insurance as a "just in case" protection, they would not cover you unless you follow the flight guidelines put out by the cruiseline. The further the port from pier or the larger the ship, the more time you'll need to plan for.