Biologically, you should not feel threatened when the threat has passed. You don't see rabbits with PTSD after getting away from the fox?

Syndrome: A group of symptoms that consistently occur together or a condition characterized by a set of associated symptoms.

Disorder: A mental disorder or mental illness is a psychological pattern, potentially reflected in behavior, that is generally associated with distress or disability

I don't want a syndrome; that divorces what I am feeling and how I am reacting from me, concentrates on/describes the symptoms, usually about something such as "Down syndrome" that cannot be helped or "treated" but are a permanent part of the person.