Do I Have Heart Trouble?...Testing has shown Conflicting inf

I saw my dr. in July with mild chest pain on my left side. An EKG was done which showed I had had a heart attack. My dr. did not believe I had. I was sent for a stress test which was normal other than slight buildup of plaque in the right artery. Was referred to a cardiologist for future reference. Saw the cardiologist and was given an EKG. This one also showed a heart attack. I was then given a echocardiogram. This was perfectly normal with no damage shown to my heart. I was told I was healthy and didn't need the services of the cardiologist. I continue to have pain on my left side. It's never bad, but a spot in my back coincides. It's more of a burning pain. I am now having a weird feeling that comes and goes. It's like being lightheaded, but I'm not really dizzy. It's very hard to describe. Heartburn has increased also. Went to the ER. I was given an EKG which was normal, chest x-ray was normal and all blood work was normal. Should I worry about this? Should I insist on more testing? Could this be anxiety because of the pain in my chest? I have never had pressure in the center of my chest.