Scared about getting braces?

Right now I really want braces (my bottom teeth are all crooked and wonky) but I'm very frightened about it being really painful, my friend said whenever she gets hers tightened she can't eat for like a week! Is this true? Do braces really hurt that badly? Do the benefits out weigh the costs? Also I'm afraid I'll look weird since most people get them on in their early teens and I'm already 17 =(.