We've been on our 4th trial of cat food with about a month's success until yesterday. Emma puked three times. The food is dark brown. Her vomit is the same color as it was with the old food (a yellowy tan that Purina One has..still a tad mixed in with the new food but not enough to amount to anything at all, I thought- a few morsals per serving of the old food). I can't understand it. At 1:00am, I heard her retching and woke up to find a big puddle on the floor. No hairballs like before, just that yellowy color. So, I decided not to give her more food this morning (just crumbs left) and she was crying and hollering like she was starving. I don't know what to do. I didn't see a hairball and the new formula is a hairball formula. Any thoughts?