Chest and neck pain.?

I been having this chest pain on the left side of my chest and it radiates through my left side of nick and up behind my left ear. I been having this for the last two months and the first time I noticed it I made an urgent appointment with my Dr. and they did an EKG test and heart attack was ruled out. A month after that I felt the same pain at a much higher level and this time I took some aspirin and rushed to emergency. They did a blood test, a chest ex-ray and an EKG test and again heart attack was ruled out and no medication or explanation was given to me as for what causes this pain. It has been about a month since I went to emergency and again the pain is far worse then the first and second time. I called my Dr. and again and explained all the symptom and he prescribed me a higher dose of anti acids which I have taken in the past and haven't noticed any differences at all. While I do feel stronger and irregular heart beats my Dr. and other Dr. at the emergency continue ruling out heart problems. I have no idea what to do next and this pain is getting more and more uncomfortable. Does anyone have any idea what this could be?