Re: Sprained Ankle and Hairline Fracture.
Crutches can be very frustrating! Try to limit the distance you have to go, so you don't have to walk as much. Make sure that they are adjusted properly. They should be a few inches below your armpit, and your elbows should be bent when you walk. You shouldn't actually put any weight on your armpits, as this can cause nerve damage. All of the weight should be going through your wrists. This can cause your wrists and forearms to get sore, so take time to stretch your wrists on occassion.
As for the ankle healing, keep it elevated as much as possible and follow your doctor's orders about how long you should be on crutches and be immobilized. Ankle sprains can be very problematic, so if you follow the directions that should decrease your risk for long term issues.
I hope that helps. Feel better soon!