it seems that you might have fracture
of some small bones at ankle joint.
You might have gone for x-ray at the time of accident and if found some fracture in small bones, plaster might have applied.
Now as more than 2 weeks passed, nothing can be done.
If there is displaced fracture, by this time there might be having mal-union.
consult orthopedic surgeon and get examined.
ok and take care.