OneLeadsToTheOther. When someone gets very anxious they tend to breathe harder and or faster.You might not even notice it if you are just taking deeper breaths.This can lead to symptoms like numbness or tingling in the fingers or hands or around the lips and even some dizziness and unsteadiness, sweaty palms, palpitations,"butterflies" in the stomach,you name it. My question to you : Why or how is it you get anxious?
Hyperventilation. Most likely is that you are breathing rapidly because of the anxiety and this alters the chemicals in your blood to cause the numb feeling. This is scary so you begin to breath faster, it is a vicious cycle. If it happens again, use a small paper bag over your mouth and nose and breath all of your air into and out of it until it stops. Good luck!