Anxiety :

Stressful situations often make us nervous or fearful. Experiencing  anxiety may help a person become more alert and focused on facing challenging or threatening circumstances. But individuals who experience fear and worry that does not subside may be suffering from an anxiety disorder. The frequency and intensity of anxiety can be overwhelming and interfere with daily functioning. Fortunately, CBT, DBT, and Biofeedback are very effective treatment strategies for the majority of people with an anxiety disorder.

Symptoms such as extreme fear, shortness of breath, racing heartbeat, insomnia, trembling, excessive sweating, and dizziness are common in the following anxiety disorders:

Generalized Anxiety Disorder
Social Anxiety
Panic Disorder
Phobias
Obsessive-compulsive Disorder
Post-Traumatic Stress Disorder