When you first get your braces on, your teeth will hurt for a few days, as they will every time you get your braces tightened or your wires changed.
Chamomile is also popular for anxiety in children. Fennel. Fennel isn't for anxiety specifically, but it is linked to treating some of the most common symptoms of anxiety, including digestion, coughing (many with anxiety have a nervous cough), and asthma (anxiety can exacerbate asthma symptoms).
Herbs for anxiety and stress relief are commonly available in grocery and health food stores as single herbs or combination remedies. You can use them in a variety of ways based on your needs and interests. Feel free to experiment and see what works best for you. If a cup of relaxing tea is for you, look for names such as Tension Tamer by Celestial Seasonings or Kava Stress Relief by Yogi Teas (one of my favorites for nervousness in social settings). Or make your own brew from loose herbs. Slowing down to make a pot of tea is very relaxing and centering in and of itself.