She has suffered an ankle sprain
an injury due to injured or partially torn ankle ligament. A ligament is the fibrous tissue that connects bones to other bones.
X ray in ankle sprain will most likely be normal.
The treatment of ankle sprain in immediate phase is RICE (Rest, local Ice application, Compression & Elevation)
You can give her brufen
junior syrup in appropriate dose if she has no history of ibuprofen allergy
You can consult orthopedician on an non urgent basis.
Hope I have answered your query.