Hello Audi!
I was quite a bit older than you are when I had my surgery, I was 20, but I was still pretty nervous at times, it's natural, everyone gets nervous sometimes. I'll be honest, the big open surgery will give you a bigger scar, and will hurt more because there's a bigger cut, and they take longer to heal. The smaller laperoscopic surgeries still hurt, there's a smaller cut and the scar is really small, and they heal quicker, but they still have to pull things about inside, which can leave you feeling bruised, and, with these operations, they have to fill you with gas, which lets them move things around safely, sometimes this can cause pain after the surgery. The good thing is, your young, so your body is strong, and you'll have lots of nurses taking good care of you, you'll have good painkillers and if you need help with any thing, no matter how small, you only have to ask. Its good to be prepared, but remember to stick to sites like this and dont look it up on google too much. Remember to be patient afterwards, you will be able to get out of bed maybe the day after surgery, but you wont be able to just get up, it will take time and its tiring at first, so make sure you ask for help.
Also, incase you haven't been warned, you will probably have a catheter after surgery, which is a tube that goes into your bladder, it collects your wee and transfers it into a bag or container, it wont hurt, and they put it in when your asleep, but it can feel a little weird when you move, especially if you weren't expecting to have one (which I wasn't) .
If you have any more questions, feel free to ask away, and if you would like a chat at all you can give me a message in the private messaging bit. Good luck sweetie!