I missed my appointment with my orthodontist.?

Don't be surprised if they charge you for that time anyway, since it was your responsibility to cancel and rebook the appointment. Most places have a 24 hour cancellation policy so they can fill the slot. Braces don't just move teeth, but hold them in place. Your teeth won't have shift back, but they also won't be improving, so you'll need to wear them longer in the end.

I hope that you called them and cancelled ahead of time. They block that time in their schedule for you and when you don't show up they are loosing valuable chair time. If you want your braces to be effective you need to make time to see your ortho for the five minutes it will take to tighten them.

That is indeed a tough question. Try speaking with someone qualified.