“Panic disorder is diagnosed if the individual has recurrent panic attacks (minimum four in a four-week period), and at least one of the attacks is accompanied by one or more physical symptoms, including persistent concern about having another attack, worry about the implication or consequences of the attack (i.e., having a heart attack), and/or a significant change in behaviour due to the attacks, such as quitting a job.7 In addition, the panic attacks cannot be due to the physiological effects of a substance or another general medical condition.”
But flashbacks may occur with other types of anxiety as well. Some research, including a 2006 study in the Journal of Anxiety Disorders, suggests that some people with social anxiety have PTSD-like flashbacks of experiences that might not seem obviously traumatic, such as being publicly ridiculed. These people may even avoid reminders of the experience—another symptom reminiscent of PTSD.
The cognitive effects of anxiety may include thoughts about suspected dangers, such as fear of dying. "You may ... fear that the chest pains are a deadly heart attack or that the shooting pains in your head are the result of a tumor or an aneurysm. You feel an intense fear when you think of dying, or you may think of it more often than normal, or can't get it out of your mind."
2.This exposure happened either by directly experiencing the event(s), witnessing the event(s) in person, learning that the event(s) happened to a close friend or loved one (note: for cases of death or near death, it must have been violent or accidental), or being repeatedly exposed to the aversive details from traumatic events (e.g., as an emergency room doctor or nurse who frequently sees dead and mutilated bodies).
Anxiety attacks, also called panic attacks, are episodes of intense fear and emotional distress that usually occur suddenly and without warning, and typically last from several minutes up to an hour. These attacks may have a discrete trigger, but they also can occur without any identifiable cause. Anxiety attacks are often recurrent, and are very distressing to the people who experience them, as well as their loved ones.
Medication: Many antidepressants can work for anxiety disorders. They include escitalopram (Lexapro) and fluoxetine (Prozac). Certain anticonvulsant medicines (typically taken for epilepsy) and low-dose antipsychotic drugs can be added to help make other treatments work better. Anxiolytics are also drugs that help lower anxiety. Examples are alprazolam (Xanax) and clonazepam (Klonopin). They’re prescribed for social or generalized anxiety disorder as well as for panic attacks.
Social Anxiety Disorder;Fear of social situations in which the person is exposed to unfamiliar people or to possible scrutiny by others. The individual fears that he or she will act in a way (or show anxiety symptoms) that will be embarrassing and humiliating, often times leading to avoidance of social situations and severe distress when participation in social situations can't be avoided. 
To the extent that a person is fearful of social encounters with unfamiliar others, some people may experience anxiety particularly during interactions with outgroup members, or people who share different group memberships (i.e., by race, ethnicity, class, gender, etc.). Depending on the nature of the antecedent relations, cognitions, and situational factors, intergroup contact may be stressful and lead to feelings of anxiety. This apprehension or fear of contact with outgroup members is often called interracial or intergroup anxiety.
Occasional anxiety is an expected part of life. You might feel anxious when faced with a problem at work, before taking a test, or before making an important decision. But anxiety disorders involve more than temporary worry or fear. For a person with an anxiety disorder, the anxiety does not go away and can get worse over time. The symptoms can interfere with daily activities such as job performance, school work, and relationships.