Wow...what a rude you know what, that GI doctor was, I can't believe that anyone would speak to you that way for one thing, I wouldn't have put up with that and I'm pretty quiet and low key in personality.
I'm not sure why Dexilant would be prescribed for you either if it's and "end stage ppi" that's what I'm trying for the first time tomorrow after being on Nexium for 8 years that stopped working for me. Maybe Dexilant is that good of a drug that it would help right away, I really don't know what to say about that, but you're right to question that, and she should have been more understanding of that right.
I'm sorry that you've joined the ranks of gerd sufferers, and it sounds like your results show that you have gerd, and that rude doctor should have explained the test results to you, but this seems like a really great forum so far for information, maybe you could look through posts and try some different things and advice. No one thing works for everyone so it's pretty hit and miss as to what works for you, it's kind of like a crap shoot, you try different things and hope that they ease your flare ups. I find that for stomach pain, along with my ppi, I take a spoonful of Gaviscon before bed. You might want to watch what you eat and see if that helps, such as acidic foods or strong spices, to much coffee, that sort of thing. Elevating your bed by putting blocks under the feet at the head board could help with keeping acid washing up into your esophagus at night, sometimes you have what's called "silent reflux" and you don't actually feel the acid doing any damage, but it sounds as though you have that, and I have the same thing. I don't know what it's like where you live, but I'd either mention that you didn't appreciate what the doctor said, and that you needed some further explanation of your results, or hunt for another doctor who isn't an ass. I'm so sorry you were treated in that manor.