Jaw Surgery!!?? (OverBite)?

Okay so I went to the orthadontist today and he said that before I get braces I should have the surgery on my jaw to make it come forward with all my upper face. Its a pretty big over bite, and I am scared for my life../: - did this happen to anyone else, what do they do when to your jaw? And just help? /: oh he said another option is a head gear but i just wear it at night but he said it isn't as good as the jaw surgery he said he does it all the time.