I got a male guinea pig last November, and since then he has shown many signs of aggression every single time I take him out of his cage to socialize or pet him. Even if I'm not even touching him, he'll chatter his teeth and shake. If I pet him he yawns to show his teeth which I've heard is aggressive and the hair on his neck sticks up. He also bumps my hand with his head if I pet him. Hes always aggressive and anxious when I take him out, even if there's nothing in the room to make him freak out. I love him but he hates me and I'd love if I could win him over, does anyone know how I can make him stop hating me?