Sometimes vaccinations have different effects on cats so your cat will probably be alright.Just remember to keep trying to give it water every now and then.If the problem persists for more than a day then call a veterinarian
Why After Vaccination Can't My Cat Walk, Eat And Drink?
It's not unusual for vaccines to have serious side affects, contact your vet to let them know what going on... I'm truly sorry for you both.
You NEED to get the kitten to the vet right away! Odds are that she is having a reaction to the shot and might not recover if you don't take her in. Hope this helps, good luck to you both.