It's is absolutely normal for newborns to pass stool after every feed, termed as gastrocolic reflex. Frequency of stool is not a concern. But what is important is if the color or appearance of stool has changed. Also if the baby seems unwell as in not taking feeds or is not active. Apart from this no investigation are warranted.
Next Steps
Continue demand breast feeding and watch for urine frequency, activity of the baby.
Health Tips
If the baby is also getting formula feeds, ensure adequate hygiene, sterilization and hand washing. This is one factor that can lead to g.i infection in babies. You can avoid excessive spicy foods.