I used to have a similar feeling in my throat just like you described. I felt like I was going to choke. GERD would normally hit me hardest when I was in bed obviously because I was laying down. I tried a lot of things and my doctor told me to do yoga and to just relax. I used to have a "perfect" CW diet which turned out to be the culprit. I changed it up and stopped gluten and dairy all together. I ate completely clean (organic fruits and veggies and lots of saturated fat). I also cut out caffeine. All of those things did the trick and I am GERD free now. I never even get the slightest symtoms anymore. I don't ever feel the need to belch, I am never bloated, my IBS is gone and my allergies are gone. I haven't even been sick in over a year when I used to get sick routinely every month. I am very strict on the primal/paleo diet and the reason I won't fall off the wagon is because I know what the consequences will be if I do.
Oh and you asked about how long it took to heal the stomach. I think everyone is a little different. I used to eat oatmeal or whole wheat cereal every day along with a sandwich with whole wheat bread. I did this for at least 3 years. I also used to do a lot of chronic cardio. So I did a lot of damage. I followed a GAPS diet which is a lot like paleo with a big emphasis on bone broths, and removing gluten/dairy completely. I think my gut healed in a little over a month. But even during the first week I felt progressively better day by day. You must be totally compliant though and if you revert back to your old diet it will just make it that much harder to regain control of it. Good luck.
"If man made it, don't eat it" - Jack Lallane
People say I am on a "crazy" diet. What is so crazy about eating veggies, fruits, seafood and organ meats? Just because I don't eat whole wheat and processed food doesn't make my diet "crazy". Maybe everyone else with a SAD are the "crazy" ones for putting that junk in their system.