Wedding Dress Advice

We are getting married in an over the water gazebo at Sandals Royal Caribbean on June 6, 2021. It will just be the two of us, no guests. I am NOT a girly girl and really don't care too much for dresses and really not looking for something super formal. I have my FH convinced I'm wearing a romper and have even shown him cute little lace rompers that actually would look great lol BUT I am totally surprising him with a dress. I have a few questions though.... first, how far in advance is suggested time to start shopping? I'm only 4'11" and have been looking on Amazon at high-low styles. I'm thinking that may be a good option in style due to my height but a little worried about the wind in the gazebo... I've heard it ranges from fairly constant breeze to calm, hit or miss. Would hate to have the dress a little shorter in the front only to have the wind lift it up! Opinions? And on the Amazon subject... has anyone else ordered their dress from Amazon or another online store rather than in person?? I have been married twice before .... however, the first one was a formal church wedding, I was young and broke and honestly got my dress from a consignment store about 2 weeks before the big day. The 2nd was a courthouse ceremony and just a very casual sundress was worn. So this is the first time I've really gotten to pick exactly what i wanted for my absolute dream wedding to my soul mate Sorry for rambling, but I know time is ticking and this is the part I'm struggling with!!!! Oh, and side note, we are having a large reception once we return and our families and children are really wanting us to wear the same clothes that we are married in so I am also having to keep that in mind as well. Perhaps I'll purchase the romper to change into following the introductions and first dances, etc