harsh

To act or speak in a rough or an insensitive manner

The father used some harsh words when dealing with his son.

moody

is a sudden change in someone's behavior such as friendly to irritable and polite to hostile

Its hard to know where a person is about if their moody.

basket case

someone whos emotions are filled with anxiety and obsession

Any mother would be a basket case if they found out their child was hit by a car.

light-hearted

a moment where there's humor and having fun

There's nothing wrong with being light-hearted at times to break the formality.

gung ho

someone who is very assertive about getting something done

Sam was gung ho about getting those packages on the truck before his shift was over.

guilt trip

a manipulation tactic by promising someone grief and sorrow if something not done a certain way

Denise ran a guilt trip on Nate by telling him to visit his estrange father in the hospital or he'll never have a chance to make amends with him.

souped

someone who gets a sudden burst of excitement and confidence based on being in favorable positon in a competition

Eric is souped because he is going to be one of the finalist.