With so few pixels it's kind of hard to see the difference between a lamb, a dog and a huge white rat. But I think the long ears and the eyes with visible whites make your lamb look more like a dog. Lambs tend not to have very visible whites in their eye.
Quick and lazy edit, because I don't have much time:
Personally, I would either go more towards 3D shapes with more contrast and large clusters of brightness and shadow or towards 2D shapes and that kind of flat paper cut-out style. Right now you have some tiny shadows with low contrast and they don't really do much, in my humble opinion. It's like a compromise between two different styles.
But I agree with fskn that the general readability is good. It's a very clean design.
