Hands and feets feel swelling after walking?

20F, 62kg and165cm, i don't smoke or drink.

I recently started walking (40min) and somewhere in between, i feel my hands(not arm) kinda stiff and a little swelled.

After the walk when I get back home(i walk at night). Even by looking at them i can say that they are a little puffy, not puffy enough for pitting.

I don't know if it's because of walking and sweating or something serious