What Causes A Hard Bump Under Ankle Bone Long After Ankle Sprain?

Hi. I am a gymnast and was climbing rope at practice. I was a 1-3 feet above ground when I decided that I would drop because I do it all of the time! But this time, I landed on the end of the rope (on the knot) which just so happened to be lying on the ground. I landed on my ankle and it gave out and twisted completely sideways. I didn t think it would be too bad because I have very flexible ankles and they sometimes do that. It turned out to be a really bad sprain and was super swollen and bruised. This happened 3-5 weeks ago and all of the bruising and the majority of the swelling is gone (it looks like a normal ankle until you compare it to my other one-- I have Very small ankles) I have gained a lot of the motion back, but still can t point my toe very well. I also have a hard bump under my ankle bone in the slightly swollen area. Do you have any idea what that bump is, or what is wrong? I have pictures of you need them you can ask for my email and email me-- Thanks.