We've had two female piggies for almost 2 months now, both are females. Recently Peri, my biggest pig, has been gaining a little weight recently and eating and drinking much more than she normally would. When you hold her up, the left side of her tummy pokes out as if something is there. She hated being held now when she used to love it, as well. She chews on everything in the cage, too. I don't know if she's pregnant or not and its getting me worried. Help?