My guinea-pig is spitting up?

These are the signs of her back teeth over growing. What happens is they grow slanted inward toward the center of the mouth so they actually end up biting their self which is causing the drooling.You need t get her to an EXOTIC vet asap as when they grind down the teeth it makes them a it sore and they tend not to want to eat for a bit, however, guinea pig can not go with out food over just a few hours of their digestive system gets into trouble and it can be fatal, it sounds like she may already having digestive problems form not eating. So Please get her to a vet first thing in the morning, please.