Are you sure it's vomiting or reflux? If it's vomiting, note that During your baby's first few months, vomiting is probably caused by mild feeding problems, such as his tummy being too full. After the first few months, a sudden onset of vomiting is more likely to be caused by a tummy infection, such as gastroenteritis. This type of infection is often accompanied by diarrhoea. So see a doctor

what you described looks like silent reflux which is same as reflux in babies. Reflux is out to turn off food to the oesophagus or stomach after feeding of feeding. Children with this should be put upright for 30mins after feeding".