Just a few questions - how much did he weigh at birth - at discharge from hospital - and now? How long has he been home from the NICU? When did the doctor do the upper GI? If it is pyloric stenosis it will only get worse as the little growth at the pyloric valve gets thicker it lets less fluids through so more come back up. My younger brother had this when he was a baby and his daughter had it when she was a baby. I would definitely advise that you find a doctor who is more receptive to your concerns for your baby.