Sprained foot 2 days ago nd there was swelling at top of the foot. This morning swelling displaced towards the ankle area. No pain but is this normal?

It is possible. Swelling and bruising may move from one area to another following an injury.
Can be normal. A sprain generates localized tissue swelling in the zone of injury. Swelling is basically a collection of fluid. Fluid around an injured foot or ankle will follow, somewhat, the laws of gravity. So, swelling from an injured foot, that may be elevated slight above the ankle, can lead to migration of the tissue swelling toward the ankle--or perhaps the ankle is injured too.
Not unusual. After a sprain different areas may swell and bruise, continue range of motion and stretching.
Soft tissue injury. Sprains of ligaments and tendon injuries require more time to heal because there is poor blood supply to these dense/thick/fibrous structures. Swelling may last for several months after such an injury.