Gerd Symptoms

Hi, I have 14 and lasts for four or five years ago I had chest pains and other stomach and arm pain. I went to the doctor who did my blood pressure, oxygen, lung capacity, heart rate, BMI and general health and said it was okay, and it is almost certainly not my heart, so little chance, it is not worth the value. They said it could be something called costochondritis. I searched the Internet for something that fits my symptoms came and I called GERD. Can someone help me suffer from GERD? Seems that my symptoms of pain in my stomach randomly, and the arms adjust downward? I also sometimes out of breath? They can relate to that? Any help is welcome. Thanks.