So much spit up

My little guy was spitting up so much before he started Zantac- then it went down to just occasional spit up. It’s been much better but all of a sudden yesterday he started spitting up a ton again. He has no fever, no diarrhea, is still producing wet diapers. I don’t know if I should just assume that this is nothing (maybe his tummy is being bothered by excess drool from teething) or if I should be treating this like a stomach virus. Anyone have experience with this?