Final answer:
Carlin is experiencing a panic attack, characterized by sudden and intense periods of fear and physical symptoms like heart palpitations and dizziness, which is not indicative of PTSD, agoraphobia, or GAD.
Step-by-step explanation:
a. panic attack:
The symptoms Carlin is experiencing are indicative of a panic attack. A panic attack is characterized by sudden, intense peaks of fear, anxiety, and a sense of imminent doom, often accompanied by physical symptoms such as heart palpitations, trembling, shortness of breath, and dizziness. These symptoms can mimic those of a heart attack, causing the individual to fear for their life.
It's different from posttraumatic stress disorder (PTSD), which is usually a response to a traumatic event, or agoraphobia, which is an anxiety disorder involving fear of places or situations that might cause panic, helplessness, or embarrassment. Unlike generalized anxiety disorder (GAD), which involves chronic and exaggerated worry about daily life, panic attacks are abrupt and intense episodes of fear.