Is there any history of trauma.. There is a possibility of severe muscle spasm / cramps which might be causing pain.
Shee needs further evaluation for reaching an appropriate diagnosis..
Next Steps
You can start with hot fomentation, take analgesic and muscle relaxant tablet, apply analgesic ointment locally at the site of pain..
Health Tips
Avoid heavy work, sitting down. Ankle and toe movement exercises can be done if pain is less..