You need to take that critter to a vet proto!
Not at all.
Most grass-eating mammals are quite large and have a long digestive tract; while guinea pigs have much longer colons than most rodents, they must also supplement their diet by coprophagy, the eating of their own feces.[73] However, they do not consume all their feces indiscriminately, but produce special soft pellets, called cecotropes, which recycle B vitamins, fiber, and bacteria required for proper digestion.[74] The cecotropes (or caecal pellets) are eaten directly from the anus, unless the guinea pig is pregnant or obese.[47] They share this behaviour with rabbits.