Go for an x-ray.. To confirm the diagnosis whether a fracture is there or not... If fracture consult an orthopaedician.. If there is no fracture,it can be a ligament injury (tear), go to a physiotherapist.
Next Steps
Go to a physiotherapist.. Ultrasonic therapy +IFT +wax therapy +some strengthening exercises will be helpful for sure.
Health Tips
At home.. Rest +hot water fomentation +pain killer gel +no long sitting /leg hanging/no low sitting +no cold exposure +no long walking /standing +no stair climbing +use ankle strap.