My cat has been throwing up on occasion. She is a very stressed kitty. Only 6 months. Very attached to us. If we go out for 2 hours or more or we deviate from some schedule, she gets highly stressed. So on occasion she will go into her litter box and throw up. She is pooping, eating and peeing just fine. Plays fine. My concern is I have the Dr. Elsey's Precious Cat Ultra Clumping Cat Litter (Dust Free) and when throwing up, she tries to re-eat her food which winds up getting litter in there. I have seen her once with litter on her chin after throwing up. I dont think she does this often but should I be concerned with the litter? What is recommended?