laugh on the wrong side of one's mouth

[laugh on the wrong side of one's mouth] or [laugh on the otherside of one's mouth] or [laugh out of the other side of one's mouth]{v. phr.}, {informal} To be made sorry; to feel annoyance ordisappointment; cry.

Paul boasted that he was a good skater, butafter he fell, he laughed out of the other side of his mouth.