God works in the parameters he decides. Surely you don't take Jesus saying that you can move a mountain literally. There are many things God answers and I myself have been witness to these miracles, but unnaturally re-growing a limb is not something he just hands out. He works in the confines of his creation and rarely goes to great lengths to contradict or inhibit that which he has set up.
Pain is good though. We can learn much through it. We can also let it turn ourselves spiteful however. Once you understand that this world is merely a trail grounds for what's to come, what exactly goes on here becomes so very trivial.