I just got an ask about scoliosis surgery and thought I'd put the answer here, too.
My scoliosis was found when I was 12. I had surgery when I was 17, the summer before my senior year of high school (you really should do it in the summer). It was ultimately up to me when to have the surgery and I definitely cried a lot while making the decision and after. It's a tough choice to make. So don't feel bad.
I was in the hospital for about a week and honestly now I don't remember the pain--morphine is a god send!
Sitting up for the first time will make you VERY dizzy. And walking is weird at first, but don't be afraid to lean on people and ask for help. I also didn't eat a lot in the hospital, but crushed ice and crushed popsicles are easy and light.
Since you'll be on a bed for a week, they're going to come in an flip you to avoid bed sores. It will be uncomfortable at first, but you get used to it.
They'll also do breathing treatments to avoid getting clots in your lungs. For some reason they do them late at night, but the treatment has a weird yet awesome taste to it.
Something I never would have thought of--your hair. If it's super short, you'll be fine. But if it's long like mine, braid it or have someone brush it. After a week on a bed, it gets horribly knotted and it'll hurt if you don't worry about it.
When you get home, if you don't have pads on your shower, put them in. And the best sleeping situation is between two walls of pillows. It'll keep you from turning but it's comfy!
Honestly, don't be scared about the surgery. Don't. It'll be fine. The recovery will take a long time, but have friends and family visit to have things to look forward to!
I watched a lot of Disney while I recovered, it's comfort TV. I suggest having movies and shows that make you feel good out for easy access.
You're going to sleep a lot which is great, it's what you need.
Now, I'm going to be honest with you. You will always have back pain. It definitely lessens over the first few years, but it will still be there. I model with someone who had it years before I did and we recently talked about how the pain/discomfort is always there.
But on the plus side, it's preventing any further damage to the inside of your body. Pain will always come and go, but your organs will now have the room they were meant to and you won't end up unable to walk.
If your curve is bad like mine was, weight might shift because you've even. You might get stretch marks from the sudden shift, but people are going to be fascinated with the scar on your back.
I don't know if one of your parents will be staying with you while you recover, but just let them know that you'll need their help, support, and understanding.
One last thing! Nurses are awesome, be nice to them and your stay/recovery will be amazing!
Good luck and don't worry too much. Cram in as much fun before the surgery as you can!