I would be a little concerned - but I'm a worrier. Is your Doc familiar with bfed infants? How often does she projectile vomit?
From Jack Newman's website:
Some breastfed babies, after the first three to four weeks of life, may suddenly change their stool pattern from many each day, to one every three days or even less. Some babies have gone as long as 20 days or more without a bowel movement. As long as the baby is otherwise well, and the stool is the usual pasty or soft, yellow movement, this is not constipation and is of no concern. No treatment is necessary or desirable, because no treatment is necessary or desirable for something that is normal.
Any baby between five and 21 days of age who does not pass at least one substantial bowel movement within a 24 hour period should be seen at the breastfeeding clinic the same day if possible, but certainly within a couple of days. If this same baby is soaking at least 6 heavy wet diapers (see #3, Urination), then baby is most likely fine and getting enough. Generally, and only as a general rule, small, infrequent bowel movements during this time period mean insufficient intake. There are definitely some exceptions and everything may be fine, but it is better to check.
New Mom to little G May 16, 2010.