Get (one's) just deserts phrase
"Deserts" is a dated word for the rewards or punishments that somebody deserves.
To gain a suitable reward or (more usually) to incur appropriate punishment for one's wrongdoings.
The killer got his just deserts when he was caught and sentenced to death.
Mary insulted a teacher when the headmaster stood behind her and heard that. And as you can probably tell. She got her just deserts.
The verb "get" must be conjugated according to its tense.
This phrase was formed based on the meaning of the noun "deserts", which dates rom the late-1200s
hurt someone or yourself
If you try to carry that suitcase, you’ll do yourself a mischief.