Is it fair that I got suspended for saying prick?

Last week during morning announcements our Principal came on the tv was doing his bull crap about making us have 5 minutes lurches for the next week so I mumbled under my breath prick and my teacher told the AP. Then like 10 minutes later I had to go talk the AP and she was like ''What's your problem?'' And I said ''Honestly he is a Dictator and is it even legal fo him to put us in a 5 minute lunch'' Then she said ''Well I can't disagree with you, but this a level of disrespect I've never seen. I said ''I've seen kids stand up and yell at teachers and cuss them out and only get 1 day of ISS, but i get 3 days of OSS?'' My parents were super pissed so my dad called the School Board and they actually apologized and said but we can't overturn you're suspension. Is this a fair punishment for saying prick?