3 months old infant.. recently changed formula from 'novalac' to 'nan' pooping continuously after every fed. is it normal?

Common: In infants it is common for them to have a bowel movement after each feed. Most important is to see if the child is behaving and responding well. If baby is sucking well, feeding well, has no vomiting, smiles and is active, there is no cause for concern. But if you remain worried take the baby to a pediatrician to have the baby checked.