cat with a stomach that looks and feels like a balloon

my normally thin cat in the space of 3 weeks has gone from being thin to having a stomach that looks and feels like a balloon she is struggling to walk and has stopped using the litter tray she just seems to stand up and do it on the spot she eats and drinks very little what could be the possible cause of this and is there anything i can do at home to get rid of this ballooned stomach

Answer from Kate
Hi, I will assume that she is not pregnant and suggest that she may have a worm problem.
https://www.our-happy-cat.com/cat-worms.html

However I do strongly recommend that you take her to see a vet as soon as possible to rule anything else out.

best wishes Kate

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