I just picked up my guinea pig Chester to let him to go play and I noticed one of his eyes are looking a little closed, and leaky. The other eye is fine, he wasn't like this yesterday. He's still his cheerful and normal self, still eating and popcorning. Help, anyone? I give him vitamin C drops daily and fresh hay and food with veggies. Would it be possibly that since I just changed the other side of the cage ( I have my boys and girls separated) and was vaccuming that it may have irritated his eye?