I am getting married on Saturday and am having major second thoughts about my hair. I have extremely thick, long hair. During my trial we put it all pinned back in a bun, similar to the first picture.

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My hair ended up falling out within a few hours because it is so thick. My hairdresser assured me that she will use industrial bobby pins and hairspray it way more. She said that it was just a trial and that the day of it will definitely not fall out. I completely trust her, but now I am feeling like I should do something to accentuate my long hair instead of putting it all up. It is going to be hot, so I definitely don't want my hair all down. i am thinking something like the second picture maybe?
What are your thoughts? Should I change and go with the second one or stick with the original style?