The correct answer to this open question is the following.
One sign of abnormality is when a person engages in behavior that creates a great deal of emotional distress or subjective discomfort.
In psychological terms, we understand "subjective discomfort" as abnormal conduct when people experience discomfort or emotional distress when doing something specific or enduring some kind of behavior. When people are living periods of emotional distress, they can recognize them by the stress it produces, and they feel anxious, irritable, they show mood swings and violent behavior.