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).
Kava (Piper methysticum, also called kava kava) is an herb that can be effective for alleviating the symptoms of anxiety. In some human studies, improvements have been seen after only one or two doses, and were maintained over the following few weeks. Don't use kava if you have liver problems (such as hepatitis), drink alcohol regularly, or take any drug with known adverse effects on the liver, including acetaminophen (Tylenol), statin drugs, and niacin.