It Was Only a Joke!

Sunday again. I wish it didn't have to be the same every week. Why can't there be different names for days? Like "Icecreamday," or "Stormyday," or even "Stupiday?" Sunday sounds so fake. Please put the word "sun" in there. As if this day is the brightest and cheeriest day in my week. IT'S NOT. It's just the day I like to call "Function/on/little/or/no/sleep/day."
The principal wasted our entire first period on a dumb teacher's meeting, so she could prep us for PTA.
She started off with flattery, as she told us what great teachers we are. She then went on to warn us that we probably have the most under-appreciated job, and that we probably have the least paying job.
I interrupted with a wisecrack, "Probably? My cleaning woman makes more than I do! My father's illegal employees make more than I do!"
I honestly meant it as a joke, and the other teachers laughed. The principal though, didn't think it was too funny.
"That wasn't meant to be said." She told me, "It was out of place and uncalled for."
I was taken aback and replied, "I'm sorry if I misspoke, but I meant it as a joke. Obviously I knew what I was getting into when I signed the contract, I'm only making fun of the fact that you used the word "probably" in this context."
The principal didn't like my explanation, and went on to reprimand me.
Even the teachers noticed that she was taking it to an extreme.
Something is going on, and I don't like it. I'm definitely being picked on.