Guinea pig has very hard belly

Question
Hi my Femail guinea pig has a very very hard belly.  She turned one on Easter.  She is eatting drinking normally.  She is pooling out fur on her belly and sides today. he belly looks bigger than it was.   When I tuch her belly she squeaks very loud and try's to move away.  Her nipples are normal also.    I was wondering if she would have a overan asyst?

Answer
Although it's possible she may have an ovarian cyst this is something we typically see in older sows.

The fact that she is eating and drinking normally is a good sign that she is not in pain. When a guinea pig is ill they start refusing to eat or drink.  

Is it possible she could be pregnant? Has she been with a male pig in the last few weeks? That could certainly account for her belly hardening, and her not wanting to be touched. If you're certain she has not been with a boar you might consider taking her to your vet to be examined.