A scenario or sitation, your own or otherwise which is undesirable or unexpected.

When someone is really funny

A person, generally female, who refers to her/himself as a Hot Mess, but in reality is not a Hot Mess because they are either not currently a mess or, more likely, they are simply not hot. Typically, the subject is under the mistaken impression they are hot.

A person whose life has fallen into disrepair. Or one who is suffering the effects of intoxicating substances, perhaps on a prolonged basis.

An overly clumsy person who seems to have no control over his/her body.

to engage in an act of self pleasure