Pain after removal of the cast is usually due to stiffness of the ankle joint. You may have pain initially but it should subside with time. You need to visit the doc if pain is persistently the same or increasing in intensity.
Cold weather aggravates pain as it inhibits blood circulation.
Next Steps
Use warm soaks to improve blood circulation to the ankle region. It's best to do your ankle exercises right after this.
Health Tips
Use over the counter medicines to stay on top of pain.