Hi and welcome.
The symptoms you described do not sound normal. She has somewhat obstruction in her gut which is not letting her feed go through and causing all that gas , cramps and vomits. One probability is volvulus ( rotation of gut causing obstruction) or congenital problems in intestine. She needs a thorough physical examination by a specialist pediatrician. I would suggest you to get her ultrasound and x-ray abdomen to rule out any obstruction. So take her to a good pediatrician so that any obstruction can be ruled out. Try to give her mothers milk and in small quantities at a time. You can increase the frequency of feeding.
Let me know if you have further questions.
Please do not forget to leave a positive rating by clicking on stars on top right corner.
Wish you good health
Thanks for the reply.
Volvulus is just one of the possibilities I mentioned. You are right, green colored vomitus is a symptom of volvulus. Sometimes, all these symptoms can be attributed her being born prematurely but the degree of the symptoms you mention, sounds severe.
The problem here is the risk of aspiration (inhaling her vomitus), which can cause very severe chest infections. So, the need to do something about her vomiting and her abdominal symptoms is crucial. If the symptoms are as constant and severe as you mention, then she needs to be seen again.
Wish you good health.