Irony

Isn't God in control of Life and Death
Doesn't He knows what will happen to us,
how we will live, how long we will live and how we will die?
If so, why do we often pray that God will heal someone in pain? in sickness?
Is there a need to pray for recovery? What if God has His plans already?
Not to heal the person..
Are we being selfish on our part and distorting His will?
We pray, hoping for a miracle... to glorify His Name
But.. are we using it too loosely, just for our own gratification
Will God change His will because of our faith?