My baby always cries when feeding and throws up when he eats formula?

He mainly feeds and I find he cries and gets fussy most when i get letdowns. I can also hear bubbly noises in his tummy so I burp him and put him back on but he still cries and stretches his body. Another thing is when I give him formula, after eating it he immediately vomits it back up. Not just spit up, projectile vomiting. What could be causing all this?