If you can, go and see a doctor or a physiotherapist immediately.
Outlined below are the exercises my physiotherapist gave me for strengthening the ankle after rolling it. These exercises are intended for people with minor ankle rolls/strains or people interested in general ankle strengthening. If you have a serious ankle injury go and see a specialist immediately, these exercises may make your situation worse if your ankle injury is serious.
Make sure that you are really confident with the easier exercises before moving onto the harder ones, jumping ahead is asking for trouble. Just like footbag you want to build up slowly to the harder stuff.
These exercises fatigue the ankle, so don't do them before a footbag session or other strenuous exercise for that matter.
Try the exercises in this order:
1. Balance on the foot for 1 minute, arms crossed.
2. Balance on the foot 1 minute, arms crossed, eyes closed. The first few times you do this you may want to hold onto a chair/rail to build up confidence.
3. Raise up onto your toes, slowly, the raising motion is like going for a datw or tatw, but much slower. You raise up from a flat foot until you are on the balls of your toes. Do 15-20 repetitions on the injured leg, immediately afterwards, do it on the non injured foot, then repeat.
4. hopping, hop only on the the same foot for 30 seconds, hop on the other foot for 30 seconds> rpt.
After doing exercises 3&4 make sure to stretch out your calf muscles:
note: ease into this stretch slowly, you should try to relax your calf muscle and point the knee towards the ground a bit. Only go as far with the stretch as is comfortable and hold the stretch until the stiffness/pain subsides.
5. Put a pillow on the ground and balance on top of the pillow with your eyes open, arms crossed, for 1 minute.
note: an ordinary pillow is fine, but be sensible.
6. With your eyes closed: raise up onto your toes, slowly, the raising motion is like going for a datw or tatw, but much slower. You raise up from a flat foot until you are on the balls of your toes. Do 15-20 repetitions on the injured leg, immediately afterwards, do it on the non injured foot, then repeat. When you are starting this one it's good to hold onto a chair or a rail to build up confidence, progress to doing it free-standing. Do the calf stretches after this one
7. Put a pillow on the ground and balance on top of the pillow with your eyes closed, arms not crossed, for 1 minute.
8. Put a pillow on the ground and balance on top of the pillow with your eyes closed, arms crossed, for 1 minute. The first few times you do this you may want to hold onto a chair/rail to build up confidence.
After doing these exercises It might also be good to stretch out your ankle: So using your hands (keep the cranking muscles relaxed), crank your ankle a bit until you feel a bit of a stretch. Ease into the stretch slowly hold the stretch until the pain or stiffness subsides.
That's pretty much it for these generic exercises, ultimately you should go and see a specialist for these sorts of problems especially if you suspect that there is ligament damage. If you feel excessive pain while doing any of these, stop and go to see a physiotherapist.
When recovering from an ankle injury it might be a good idea to lay off some of the more strenuous ankle cranking moves(walkovers, frigid, zooming, etc) for a while until you are confident in your ankle's strength.
Best of luck with your recovery.
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