Hey guys, I have recently switched my cats food to the stuff you get from the vet due to crystals in his pee. We have two cats - Socks and Charlie. Charlie is 3 and Socks is almost 2. Anyways, we switched and the odd time Charlie will throw up after he's finished eating and he keeps peeing and I don't know if it's because I'm not giving him enough and he's hungry or because he doesn't like the food, before they were eating special kitty cat food, and he was fine. Is this something I should call my vet about and switch to something else? Also socks has been fine.