Why Does My Kitten Growl When Eating?

I’m having problems with my kitten, she is just a little over 2yrs old. I have not had her for very long but i have noticed that when she eats it sounds like she is growling or purring to me. What should i do? My cat was throwing up yesterday and today I realized he’s been acting weird lately. He won’t eat his food, he tries to hide from the family by rolling in the dirt or on our carpet, sometimes he gets grumpy all of a sudden(like one day), and most recently he has started running away from us so we can play together (he doesn’t run while we are playing). We’ve done some tests at the vet and everything seems fine except we don’t know what else it could be besides him possibly being sick…