Hi, thanks for writing to HCM.
Based on the description, I suspect that you could have suffered a subperiosteal hematoma
(blood clot beneath the outer layer of bone). This will take some time to resolve (may be 4-6 weeks) and in general , will not cause any problem. Apply a compression bandage over the swelling to hasten the resolution process.
Swelling in the ankle is a normal finding after any injury
to the leg and is a part of the injury & inflammatory process. Use of compression stockings or elastic bandages will help in resolution.
Foot end elevation is advised, most of the times in a day
Hope this information is helpful. Good day