Lots of spit up😳

How do you know when they are spitting up too much? I have a 6 week old, fussy, colic baby (Ebf). I've cut out dairy which has helped a lot but I'm concerned about how much he spits up. Sometimes the milk comes back up righ after he eats, sometimes it's later and it's curdled. I can often here his tummy rumbling but he has a ton of wet and dirty diapers and is growing well so I assume he's getting enough even with all he spits up but I'm still worried cause it seems like so much! Any tips?