My 5 week old male guinea pig started dragging his hind end yesterday. He is also laying on his side and not really moving around his cage. He eats if I put him in front of his bowl. I took him to the vet and they did an xray which showed no fracture or break. He has a slight fever and swelling in his thighs. The vet said it could be a virus of the brain such as meningitis. He is keeping him there tonight and giving him meds. Does anyone have any help they can offer me? I am really worried and the vet is unsure what is really going on.