crazy doctor!

So for my babies two month well-baby check up we saw a new doctor. She asked if my son was sleeping through the night (about 6 hours straight) and I said sometimes, not always yet! (He is formula fed) he was actually on a good schedule.. went to bed at around 10, woke up at 4 then again at 7. She said if he woke up in the night not to feed him any formula.. to only give him water (4 oz or so) and I was stunned! I read that this is not safe.. what do y'all think.. should we continue to see her?