look as if one has been dragged through a hedge backwards

(idiomatic, UK) To look very disappointed.

(chiefly, Ireland, Northern England, slang, mildly, vulgar, simile) The face of someone who looks depressed.

If someone looks like death warmed over, they look absolutely terrible — pale, hollow-eyed, barely functional, as if they just crawled out of a sickbed or survived a seriously rough night. The phrase conjures the image of someone who is technically still alive but not looking like they're especially glad about it. It's used both for genuine illness and for the kind of exhausted wreckage you see after an all-nighter or a bad hangover. Common across North America and Canada.

(chiefly, US, dated, idiomatic) Having no physically attractive characteristics, but not blatantly ugly; very plain in appearance.