What type of episode was Warren experiencing while waiting in line for a rollercoaster ride when he began to sweat and tremble?

Warren's experience of sweating and trembling while waiting in line for a rollercoaster ride indicates a panic attack. A panic attack is characterized by sudden and intense feelings of fear or discomfort, accompanied by physical symptoms such as sweating, shaking, rapid heart rate, and trembling. These symptoms typically occur unexpectedly and can peak within minutes, creating a feeling of impending doom or a sense of losing control.

The context of Warren waiting for a rollercoaster suggests that he may have felt overwhelmed by fear or anxiety related to the ride. The bodily responses he is experiencing are typical of a panic attack, which may occur in anxiety-provoking situations even if the actual threat is not present. Panic attacks can be a standalone episode or a symptom of a larger panic disorder, but the question describes a specific event, making "panic attack" the most appropriate choice.