My gallstone attacks always started feeling like reflux but then progressed from there. Taking Gaviscon normally sorts out reflux in about 30 min, but when I was having the gallstone attacks it made no difference, except for making my vomit all fresh and minty LOL (because gallstone attack always progressed to vomiting and writhing around in pain). And yes gallstone attacks can be intermittent, but they tend to be set off by either fat/oil or alcohol. So no fish and chips.

I think if you're still concerned about GERD, your dr will suggest getting onto a GERD medication. If you've been taking that regularly & then you have an attack that would suggest the symptoms are caused by gallstones.