You are absolutely right. God has His own plans and no foolish astrologer or a doctor can manipulate it. You did a wrong thing by preponing the delivery. However whatever you do the baby will be born at the appointed time. The time of birth of the baby should be taken as the time when the baby gives out the shrill cry for the first time which initiates the baby’s own breathing process which lasts till he dies, again the date of death can also be never predicted by even the best doctor in the world. God has His own ways of sustaining this universe and no living being can alter it.