get one's knickers in a twist

Verb

 * 1)  To become overwrought or unnecessarily upset over a trivial matter.

Usage notes
This is one of the most variable of all expressions, as the familiar rhythm carries the meaning regardless of the individual words used.

Undergarments ranging from gussets to diapers will work, though the most commonly used are women's undergarments, especially and its synonyms, even when the addressee is a man. Given the right context, even this rule is not steadfast; a children's book and a line from a children's TV show both used the phrase don't get your tutu in a twist.

Likewise the word at the end can be anything similar in meaning to bundle; twist; knot; wad.

Translations

 * Finnish: vetää herne nenään
 * French: avoir ses bobettes dans un tapon, slaquer ses bobettes
 * German:, auf 180 sein, einen (dicken) Hals kriegen
 * Italian:, innervosire, , , ,
 * Spanish: hacerse la picha un lío, hacer una montaña de un grano de arena