My baby is 3 day's old she is on a mixture of breast and formula but she has has diarrhea last 2 dayx will this settle or does she need to go to the d?

Newborn poop: Newborn poop is very watery and should soak right in to the diaper, especially if she is breast feeding. It can be explosive, very liquid and happen a dozen times a day. This is not diarrhea, this is normal newborn poop for a 3 day old. No need to take to doctor for this. Talk to doc at next appointment about what to expect for normal stools in the first few months of life.