Posted by Joel on November 17, 1999
In Reply to: "I'm gonna have a fit and fall in it" posted by Scott on November 05, 1999 : My Gradmother uses this one all of the time when she is flustered.
: Anybody ever hear of this one? Got a source?
I'll take a guess, but qualify it as just a guess.
It sounds like a play on words involving a rhyme, namely "fit" and "pit." A pit is something you can fall into. And there is no problem understanding the phrase "I'm going to have a fit." I'd guess it just combines an ordinary phrase with a rhyming pun.