Ankle injury. Injury and ligament tear?

In 2015 January, I had sprain which the doctor I consulted said was a ligament injury. It took a long time to heal but my ankle always pained when I used bend on it while sweeping up dust onto the dustpan or when I use the Indian style toilet. I injured the same ankle many times, some were just mild twists which pained and just faxed quickly and two which swollen up but got better in two three days and one, which happened recently (in may). Unfortunately, it turned out to be another ligament injury. Now I can walk around, but not very fast. I can't run and also can't climb the steps fast. The doctor I consulted said I don't have to worry about it but honestly I am very worried. I just want to know what I have. Do I have a grade two or three sprain ? Do I have ankle instability ? If yes, are there rehab exercises which I could do ? Doctors who see this message, please do reply. Really anxious and waiting. Also, what's the difference between ligament injury and ligament tear ?