My main symptoms are back pain,( due to a slipped disc) and pain behind my sternum. My chest pain is almost constant like yours. I have been able to sleep but wake up . I have known mild GORD and weak esophagul motility which was discovered on one of my many tests over the years. You might be having motility problems that can't be seen on endoscopy as this is often found in fibromyalgia patients like us. I infact did see my gastro consultant the other day and I was expecting to be signed off back to care of GP but he is keeping me on his books as I think he wants to make sure it doesn't get worse. I had visible reflux seen during endoscopy but if nothing was seen during yours it doesn't mean that your motility isn't affected. If there was no acid leaking up I wouldn't go down the ppi route for GORD. I don't take anything as the side effects for me are terrible. I am no doctor but definitely looks like you have a motility issue or are just very sensitive to the movement of the esophagus. I take gaviscon only for the acid, which doesn't help much . I can relate to your suffering. Chocolate, fatty foods acidic foods and eating just before bed is no good but you probably know that already. I feel almost every thing going on in my body especially when food slides down the hatch. I haven't quite figured out how to deal with it like you but I do know that it's highly likely the fibromyalgia and possibly a motility problem . I eat boring things when suffering like soup, drink lots of fluids wile eating and because I like coffee drinks decaf. It's easier to have easy to swallow food, high in calories.
Thinking of you in your suffering, as I write this I too have my chest pain..... What does the trick for sleeping is co codamol just before bed but this obviously isn't a long term solution.
I hope it becomes more manageable soon.
One last thought is could you be intolerant to gluten?, it might be worth going down this route even ìf you're not celiac.
Best wishes Guinea pig lover.x