Cat threw up live worms, no appetite

I am taking care of a female cat that was recently spayed, given de-worworming and flea medications and vaccinations (on the 13th of May). This morning she threw up pink bile that had live worms in it, and hasn't eaten all day. I will call the vet on monday. Until then, does anyone know if this is a normal reaction to de-worming medication?

Yes, it can be, especially if she had a huge infestation of parasites that are now dying from the medication. Once they start to die the body will flush them out, usually in the stool but if there's a large number of them sometimes the pet can vomit them up too. Dying worms will still wriggle around, and live healthy worms rarely leave their host so the wiggly worms you see in the vomit are most likely dying ones. What did the worms look like? Like thin spaghetti or short and fat like grains of rice? The long skinny ones are likely to be roundworms and rice like ones are tapeworms. Find out which dewormer the vet gave and make sure it's appropriate for the kind of worm you see. Different medications kill different worms. Hope your kitty feels better soon!

Thank you @CatLadyVetTech  I'm relieved to hear that. She seems to be feeling better today. She's eating normally and is hanging out on the couch asking for attention. She was a stray that I took in when she had a litter of kittens (and developed an abcess on her hind leg) so I don't doubt that she did have a huge infestation.