My daughter born on 02 august 2016, preterm, 36 week 6 days, 1.92 kg. We are bottle feeding her expressed milk since she would not direct breastfeed. After 15 days, we gave her 1 feed of formula after which she threw up after 2-3 hrs. Since then she vomited 2-3 times continuously. And at 4th feed, she is hungry like anything but refuses to take feed by bottle or spoon. She spits milk from her throat and does not swallow. Before this issue, she used to take expressed milk by bottle by had only hiccups after feeds. Please help.