My baby is 5 weeks and fed mostly by breastmilk. A few ounces of formula a day only. This past week she went a few days without pooping and then started going once a day. Does this look normal? It seems way more runny than normal. We did see the doctor and they said to only be concerned with no poop for 5 days. Also she grunted and pushed real hard to get this out but it's so runny??