My daughter is 5 months old. She was born early but was large 9.0 lbs. she's getting 7 oz of formula 4 times a day. She seems to be waking up hungry in the night now when she used to sleep through the night. My dr is adamant about starting food no earlier than 6 months. Is it really bad to start pablum now or should I still wait? She holds her head up and sits in her highchair already..pls help!