'evening, all!! Emz, like Lottie says, it sounds like your little lass is in season, but I don't think this would cause her to wee all over the place. Pop her down to the vet's in case she has a urinary infection.
Like you, sheribee, I lost a lovely little cat (Monty) last summer through cystits. It can cause all sorts of problems and kill very quickly. I think male cats are affected worse than females, although it may be more common in females. If Monty had lived, he, too, would have had to be on a special diet - I've still got the food my vet gave me for him. Good luck with your kitten, Emz and keep us posted as to how she is, won't you? K x