The theologian Paul Tillich characterized existential anxiety[23] as "the state in which a being is aware of its possible nonbeing" and he listed three categories for the nonbeing and resulting anxiety: ontic (fate and death), moral (guilt and condemnation), and spiritual (emptiness and meaninglessness). According to Tillich, the last of these three types of existential anxiety, i.e. spiritual anxiety, is predominant in modern times while the others were predominant in earlier periods. Tillich argues that this anxiety can be accepted as part of the human condition or it can be resisted but with negative consequences. In its pathological form, spiritual anxiety may tend to "drive the person toward the creation of certitude in systems of meaning which are supported by tradition and authority" even though such "undoubted certitude is not built on the rock of reality".[23]
Anxiety is distinguished from fear, which is an appropriate cognitive and emotional response to a perceived threat.[12] Anxiety is related to the specific behaviors of fight-or-flight responses, defensive behavior or escape. It occurs in situations only perceived as uncontrollable or unavoidable, but not realistically so.[13] David Barlow defines anxiety as "a future-oriented mood state in which one is not ready or prepared to attempt to cope with upcoming negative events,"[14] and that it is a distinction between future and present dangers which divides anxiety and fear. Another description of anxiety is agony, dread, terror, or even apprehension.[15] In positive psychology, anxiety is described as the mental state that results from a difficult challenge for which the subject has insufficient coping skills.[16]
Foster the development of a strong peer network. It's probably no surprise to hear that peer relationships become a major source of support during adolescence. Encourage your child to engage in interests (like arts, music, and sports) that will help them develop and maintain friendships. If your child already has a very busy and structured schedule, try to carve out some time for more relaxed socializing. However, note that sometimes peers can be the source of anxiety, whether through peer pressure or bullying. Check in with your child about the nature of their relationships with others in their social circle (school or class).

People with panic disorder often worry about when the next attack will happen and actively try to prevent future attacks by avoiding places, situations, or behaviors they associate with panic attacks. Worry about panic attacks, and the effort spent trying to avoid attacks, cause significant problems in various areas of the person’s life, including the development of agoraphobia (see below).