Please rest the foot, apply ice pack on foot, take non-steroidal anti-inflammatory such as tylenol, ibuprofen, or naproxen, do not bear weight on foot, and keep the leg raised on a stool or sit on the bed with leg popped on 2 pillows. Meanwhile set up an appointment with your doctor. You will probably need X
or MRI. There may be a ligament tear or minor fracture or arthritis that has got aggravated. Please consult your doctor regarding this. Take care!