As long as I can remember, I've had leg pains in the exact same spot, being my inner calf. As I've grown up though, it seems that it changes a bit. Its always the same spot, but it now start in one leg (typically my ankle), moves up it, then switches to the other side, down that side, to that ankle.
6 weeks to fully heal to be able to change the earring. cartilage piercings take longer to heal than some other piercings. 6- 12 months is standard. A year is not uncommon either. If you take it out even when it is fully healed and leave it out for too long the hole will close up and this can happen very quickly. http://en.wikipedia.org/wiki/Body_pierci...
The Mayo Clinic recommends leaving earrings in place for at least six weeks after the piercing, with other body piercings possibly taking longer to heal. It is recommended that you leave the piercing in place to prevent the new hole from closing. Once the piercing heals, you can switch the earrings out.