Dear patient You have got injury to your shin through motor vehicle accident which is high velocity trauma. Since you are able to walk on limb with pain possibility of minor fracture cannot be ruled out. I would advise Xray of involved leg anteroposterior and lateral views to rule out fracture. If it s normal apply cold compress hourly on swelling. Take tab diclofenac plus serratiopeptodase combination twice a day for pain and swelling relief. Take tab augmentin 625 mg thrice a day for 3 days to prevent infection. If there is fracture need to consult expert orthopaedic surgeon.