Ok, so Marcie is an indoor cat. I have had her for almost a year and she is up to date on her shots. I can't see how this could happen, but this morning I saw a something that looked like a grain of rice on her butt. I wiped it off and on closer inspection, it seems to be a worm of some sort. How in the world could she get this? Is it because she occasionally eats bugs that she hunts? Can this wait until Monday when the vet is in? Is there an over the counter type thing that I can buy in the pet store?