Round face are suitable for frames with oval, rectangular, or square shape (but prevent small, round glasses). But you can try some on in the brick and mortar stores to see if other styles of frames is suitable.
oval sunglasses are not a bad choice because they work well on your small round face. But sometimes, you will probably find it too ordinary because everybody with a round face around you wears such sunglasses and you cannot be distinguished from them. So it is up to you to make a change when you discern that scene.