One of my rats has suddenly gone a bit mad. He always had a lot of energy but last couple of days he's gone very erratic. He runs around the cage like a madman (not all the time) and this morning I noticed he had a case of cage rage: he tipped over the potty, food bowl onto another floor, food all over the place, just basically ran riot. I think his cage mate seems a little scared of him as once I saw him jump up onto a platform away from him. I haven't seen any actual serious aggression between them though. I've had them less than a month so I don't know if it's his "time of the month" or something. He's not aggressive towards me and doesn't bite.