A grade II or moderate sprain causes partial tearing of a ligament. The patient has bruising, pain, and swelling. A person with a moderate sprain usually has some trouble
putting weight on the foot, and there's some loss of function.
Patients who have a grade III or severe sprain completely tear or rupture a ligament. Pain, swelling, and bruising are usually severe. The patient can't put any weight on the joint. An X-ray is usually taken to rule out a broken bone. MRIs tell if the ligament is torn partially or completely.
The long-term outcome of your ankle sprain depends on how severe it was and how it was treated. A broken ankle is more likely to lead to arthritis, especially if it's not stabilized with treatment. It sounds like your symptoms are getting better over time. That's a good sign that you will recover without further problems.