Yes, if it shakes it head, that means your tama is at its base weight and can't lose anymore pounds (games make you lose weight) If you want to play games, feed your tama snacks or meals to gain weight.
NOTE: If your tama eats too many snacks, it can get a toothache (adults and babies don't get toothaches.) Also, sometimes, your tama will refuse meals if its not hungry or is full. (Tamas do not refuse snacks unless it has a toothache.)
tamasrock123