DS has always been a little gassy, but just this past week he seems like he's really in pain. He doesn't burp easily, but I try to burp him after each ounce of his bottle. Partway through most feedings, he starts getting REALLY fussy like his belly hurts and he farts a lot. Then he continues with lots of gas and spitting up (which also just really started this past week) after his feed.

Yesterday I bought Gripe Water and Mylicon and so far it's not making a difference, but it's only been a day. How long does it usually take for it to work?

He's currently on Gerber Good Start. Which is what I usually hear is what people switch to for gassy babies, so I guess if it's a formula issue the next one I would try is Similac Sensitive? DD had a milk protein allergy and needed Similac Alimentum- which is stupid expensive so I'm hoping it's not the same issue. But, in addition to tummy pain and gas, she had explosive diarrhea and persistent projectile vomiting (which was super fun), and he has neither of those.

Any advice?