I'm 15, and though I can't help much about the first part of the question, I would say bring a friend with you
I've had my mom and brothers (they wanted to see the laser) come in with me before, and the doctors were totally ok with it.
Also, don't be nervous
with some of the new lasers they have, I can barely feel it. I used to get nervous, but I'm actually looking forward to the treatment tomorrow, because I know I'm one step closer to having it completely gone