shit yer snatch
To completely overreact to a situation. Obviously meant to apply to women but doubly effective when applied to a man, implying they are, in fact, actually a woman.
Thomas: We're going to be late again! We have to leave and you're still sorting mail and need a wash!
Percy: Ok, don't shit yer snatch! The fat controller can wait two minutes!
Percy: Ok, don't shit yer snatch! The fat controller can wait two minutes!