One thing you ought to know about booking shore excursions.
If you do it on your own, on line, it is often less expensive than the cruise line excursions HOWEVER, if you happen to miss that port, because of weather, or whatever, you lose your money. If your excursion is late back to the ship, and the ship is gone, too bad...........you have to pay your own way home or to the next port to meet the ship. If you go on a ship's excursion, the ship will WAIT for you, if you are late, and they will refund your money if the shore excursion is cancelled for ANY reason. The other thing is that you can cancel your excursion, on board, 24 hours in advance, and you cannot do that if you book your own tour.
I'm not trying to scare you, just to point out something that noone else has pointed out.
Also, don't panic about your clothes. Your clothes will be fine. Noone has seen any of them before. People wear anything from shorts, capris, slacks, jeans during the day, and everything from "church" clothes, to dressy pants suits, to formal ball gowns in the evening. If you feel dressed up, you ARE!!!!
Your shoes are fine................whatever they are................you see tennies, sandals, loafers, dock shoes, flats, low heels, and spike heels at night..............be COMFORTABLE on that moving ship. The distances are far on a ship, and walking from one end of the Star, to the other, when its moving, in stilletto heels can be very uncomfortable..
Best thing about a first cruise is that it's a first cruise!!! You'll have a wonderful time, and there wont ever be another cruise, however delightful, that lives up to that first cruise. Wonderful...................
Have a great cruise, and don't WORRY!!