Neuroticism, one of the Big 5 personality traits, is typically defined as a tendency towards anxiety, self-doubt, depression, shyness, and other similar negative feelings. Since all personality traits, including emotional instability, exist on a spectrum, everyone is a little neurotic to some degree—some people are just much more neurotic than others.
Some self-deprecating comedians and complainers wear their neuroticism as a badge of honor, but in truth, the negatively biased are more prone to mood disorders, loneliness, self-consciousness, and hypochondria, to name just a few behavioral tripwires. In reality, neuroticism is rarely fun for anyone, though some research has shown that neuroticism can predict student success, and may be correlated with certain reproductive benefits.
Neuroticism may have provided evolutionary advantages, as well—paying more attention to negative outcomes could have helped certain early humans survive over others. In the present day, however, it may be a better choice to laugh at one's hang-ups rather than run away from them.