uptight

Excessively concerned with rules and order, always serious.

Don't be so uptight! You won't go to jail for crossing the street against the light.

Emotionally repressed; nervous and tense.

Sexually repressed.

He came from a very uptight religious background, but you wouldn't know that now!

Unfriendly or rude.

Withnail: Just because the best tailoring you’ve ever seen is above your fucking appendix doesn’t mean anything. / Danny: Don’t get uptight with me, man.

An uptight person.