You need to talk to a GI doctor. It has taken me about 3 years of going back and forth to differant doctors before I finally got one to perform the tests for GERD. He did the scope down my throat and said I had a hiatal hernia and did a delayed emptying which did determine that I do have delayed emptying. He then gave me medications. None of them worked for me. He would change tell me to elevate my bed and watch my diet. Still had the same problems but then they began to get worse. I had several bouts of severe chest pain and was life flighted to the hospital because they thought I was having a heart attack. I had several cardio tests done and they confirmed it was not cardiac related but must be gastro intestinal. I finally got an appointment with another GI who did scehduled some further testing, took me off the medications I was on since they weren't doing anything for me. He told me he would find the problem and we would figure out how to fix it. Gaviscon was the only thing that had helped me at all, but even it doesn't help like it used to.
I also have the cough and constant clearing of my throat, I have the feeling of something caught in my throat. Keep a list of what you are eatting, when you have your attacks and what your symptoms are. This will give you a starting point when talking to your GI. The GP that sent me to the GI is a fantastic doctor and instead of trying medications all over again, he sent to a specialist. I regret not having asking for a second oppinion, when I was not getting anywhere. Good luck to you Keep us posted as to what happens