1
general::
Phrase(s): have a fit [and] throw a fit
to be very angry; to show great anger. (See also have a conniption (fit).) • The teacher had a fit when the dog ran through the classroom. • John threw a fit when he found his car had been damaged.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Also, have fits or a conniption fit;take or throw a fit;have kittens. Become extremely upset. For example, She'll have a fit when she sees Anne wearing the same dress, or Mom had a conniption fit when she heard about the broken mirror, or Don't take a fit? the car's not really damaged, or Jill was having kittens over the spoiled cake. One can Also give someone a fit or fits, as in His dithering about punctuation is enough to give me fits. Fit and fits, along with conniption fit, have been used in hyperbolic expressions to denote a bout of hysterics since the 1830s; throw a fit was first recorded in 1906, and have a fit in 1924; have kittens, alluding to being so upset as to bear kittens, also dates from about 1900.
American Heritage Idioms