To the original poster, I have these identical symptoms and for me YES they were due to low stomach acid, enzymes etc., and just so you know you shouldn't really drink apple cider unless it's...
I just stumbled on this post online and I can see it's old, but I just wanted to let the original poster know you helped me! I get a nasty headache when I take the Betaine HCI with Pepsin. Thought I...