Wondered if anyone could help please. We have a GOS, 12 weeks old , one of 10 in the litter. Tonight he was shivery and wouldnt eat. Temp was normal. He is one of the smaller ones but always keen and noisy at feed times. Tonight he just stood looking out of the arc looking really sad....tail straight. I am wondering if it could be worms? Bought this litter in at 8 weeks and thought they had all been wormed but suppose, if it was powder, he could have missed. Any ideas please?