Seeing your query..and all your evaluation with doctor
I feel your child may not have any illness
.. u have seen similar cases previously..
Check these things.
1. Does your child vomits after all meals.. I mean things he like food that he or she eats
2. Some children are offended by smell , taste of some food . If child dislikes some food they like to vomit
3. Or are u overfeeding the child. ?
4. Don't let child lie down immediate after meals..
5. Does ur child has constipation ?
Does he consumes junk.n fast food more ?
5. Check these..
U don't need to panic I gues..
This could be a behavioural problem and may disappear with increasing age
Thank you