Element fire

Anxiety and mental illness in general are a misuse of the energy of fire. When you feel anxious, part of your body may feel hot like the heart or the head. Your heart might be racing because it is processing a sudden flow of blood that your brain is needing. This results in inflammation which is an excess of fire energy.

In order to redirect that energy in healthy proportions, you need to balance this fire by adding the energy of all of the other elements into your system (see other elements).
The fire energy makes your energy unsettled and scattered. Use this energy to bring air, water and earth energies into your system.
Instead of turning around in your house, go out for a run. Exercise will bring you oxygen and ground you. If you can be barefoot in the grass, practice chi-gong or tai chi to manage this overwhelming fire energy. If you have access to water, go swimming.
In any case, move. Especially if you have sleeping issues, you got to exhaust yourself physically. Most likely, you are not used to exercising so much. This anxiety is telling you it is time to change your habits and move your body. Do it at your rhythm but do it every day.
The energy has been stuck in your body for a long time and has turned into anxiety in an attempt to move through. Let it move through in a healthy way.

On an emotional level, anger is fire. Some anger might be trapped in your body. It might be useful to look into it and exercise your anger out. There are many exercises you can do for that. That includes boxing, punching, screaming...

Singing and dancing will also help you move this energy through.

Do you express your desires in a healthy way? Do you harness the fire in your guts to live a life on purpose and express whatever your soul wants to manifest? What is your relationship with desire? Do you know how to say no?

And most and for all, your nervous system is inflamed because your guts are inflamed. Do not blame yourself, we all did it. Junk food, stress at work, alcohol, pharmaceuticals, and lack of knowledge of what anti-inflammatory food is, your "second brain" is in a constant state of PTSD, trying to cover up the damage that is put on it every day.

If you are suffering with anxiety, you need to change your diet asap. Most likely your guts are filled up with holes created by toxic proteins that you bring through your diet. These proteins are called lectins. When your gits are pierced like a swiss cheese, you are allowing unhealthy bacterias and toxins go into your blood stream. By removing lectins from your diet, you will allow your gut wall to repair itself and won't overload your blood with toxins, creating an immune response.
Success guaranteed. Your guts need to be refilled with healthy food, healthy bacterias, those that help you with digestion, process toxins and help eliminate them out of your body. 

Fire is a powerful energy. When harnessed properly, it can propel you to your highest potential and open your psychic abilities. In order to have a healthy relationship with your inner fire, you need to learn how to direct that energy for your best interest. This means cleansing your body from inflammation and practicing your emotions and spirituality out.
We are not programmed to run around in stress in order to satisfy someone else's schedule or deadline. Originally we are meant to live our life in connection with the divine and to eat the food from the earth that is good for us. In every culture of the world, people used to dance and sing their connection to the divine. They used their inner fire to express themselves sensually and sexually and to manifest their devotion to the good. This is what we need to learn to go back to.