my baby doesn't gain weight propperly during the last 2 weeks. He coughs or chokes then leave the breast for just a few second each time he gets thru the breast. My doctor orders an upper gi for him. I wonder anybody else has the same situation. My baby is now 4 months and 2 weeks. He spit up or throw up occasionally in the past and I don't know why it's getting worse. He didn't have reflux at birth though ?? please help!

Just don't really want to have my baby suffer from the X-ray.