Since you saw the queen mating with a drone then the queen you saw must be a new queen that will eventually make a colony next year if it survives winter.
The existing queen has no need to mate again.
Once the colony is up to size new queens and drones are produced that are forthwith expelled from the colony spending the summer after mating feeding while remaining outside their original colony.
The drone dies after a week or two but the queen will hibernate when the weather cools in the autumn and begin the cycle again early next spring.
I've no information but as it's still quite early in the season it could be that the new queen will attempt a new colony right away.