Hello
I am sorry you are feeling this way and I know how scary this is. I deal with it often. I have had so many EKG'sI can't even count and nothing has every showed up.
My Dr. is awesome and so kind hearted when it come to me and my PA's. He has reassured me so many times that everything is ok. I have a fear of fainting also and nothing has ever happened.
Hang in there.
And feel better
Just try and relax I know how hard that can be though