Selective mutism: A somewhat rare disorder associated with anxiety is selective mutism. Selective mutism occurs when people fail to speak in specific social situations despite having normal language skills. Selective mutism usually occurs before the age of 5 and is often associated with extreme shyness, fear of social embarrassment, compulsive traits, withdrawal, clinging behavior, and temper tantrums. People diagnosed with selective mutism are often also diagnosed with other anxiety disorders.

Physical Symptoms: People with panic disorder may also have irritable bowel syndrome, characterized by intermittent bouts of gastrointestinal cramps and diarrhea or constipation, or a relatively minor heart problem called mitral valve prolapse, which can trigger panic attacks in some people. In fact, panic disorder often coexists with unexplained medical problems, such as chest pain not associated with a heart attack or chronic fatigue.
In an anxiety-related disorder, your fear or worry does not go away and can get worse over time. It can influence your life to the extent that it can interfere with daily activities like school, work and/or relationships. Fear, stress, and anxiety are "normal feelings and experiences" but they are completely different than suffering from any of the seven diagnosable disorders plus substance-induced anxiety, obsessive-compulsive disorders, and trauma- or stressor-related disorders.

Situationally predisposed panic attacks don’t always occur immediately upon exposure to a feared situation or cue, but the individual is more likely to experience an attack in such situations. For example, a person who has a fear of social situations but who does not experience a panic episode in every social situation, or who experiences a delayed attack after being in a social environment for an extended period of time.
Before SSRIs and SSNRIs became available, medications from the group known as the tricyclic antidepressants (TCAs) were often used to address panic disorder. Although TCAs have been found to be equally effective in treating panic attacks, SSRIs and SSNRIs have been proven to be safer and better tolerated. Therefore TCAs are used much less often than they were previously.
Anxiety can be either a short-term 'state' or a long-term personality "trait". Trait anxiety reflects a stable tendency across the lifespan of responding with acute, state anxiety in the anticipation of threatening situations (whether they are actually deemed threatening or not).[40] A meta-analysis showed that a high level of neuroticism is a risk factor for development of anxiety symptoms and disorders.[41] Such anxiety may be conscious or unconscious.[42]
An anxiety attack can be described as a sudden attack of fear, terror, or feelings of impending doom that strike without warning and for no apparent reason. This strong sensation or feeling can also be accompanied by a number of other symptoms, including pounding heart, rapid heart rate, sweating, lightheadedness, nausea, hot or cold flashes, chest pain, hands and feet may feel numb, tingly skin sensations, burning skin sensations, irrational thoughts, fear of losing control, and a number of other symptoms. (While other symptoms often do accompany anxiety attacks, they don’t necessarily have to.)
Separation anxiety disorder: Separation anxiety is often thought of as something that only children deal with; however, adults can also be diagnosed with separation anxiety disorder. People who have separation anxiety disorder have fears about being parted from people to whom they are attached. They often worry that some sort of harm or something untoward will happen to their attachment figures while they are separated. This fear leads them to avoid being separated from their attachment figures and to avoid being alone. People with separation anxiety may have nightmares about being separated from attachment figures or experience physical symptoms when separation occurs or is anticipated.
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