The baby may cry for many reasons, not just hunger.
If the baby vomits after a feed, maybe he needed just pacification. Have you tried a pacifier?
One of the important things that the French parents do is to practise a pause. Wait at least 20 seconds to a few minutes before picking your baby up. This will give him some time to self-soothe
If the baby is crying, carry out this check and see if the baby stops crying. If not, move to the next point.
1. Check the diaper if it is soiled or wet. If yes, change the nappy.
2. Check the back of the neck to see if the baby is too hot or cold. If yes, make the baby more comfortable.
3. Check if the baby is hungry - offer a pacifier/your little finger and see if the baby is pacified. If not, offer a feed
4. Check if the baby is uncomfortable due to something else - even tags on the clothes can cause distress to the babies
5. Check the baby to see if there are other signs causing distress
Hope this helps.
Alvin Ng