My male guinea pig, who is just over a year, is behaving extremely frantically. I heard some noise from his cage which woke me up, and when I went to pick him to see if he was ok, he ran as fast as he could into the bars on his cage and fell backwards. He also frantically ran around his entire cage, smashing into everything in it. I have no idea why this has happened all of a sudden. If I put my hand in the cage, he doesn't sniff it as he usually does. If I try to pick him up he is terrified. I've emptied the entire cage because I'm worried he will hurt himself severely and hes just sitting in one corner, he won't move at all. It's almost as if he's seen something and it has deeply scared him.