You made the right move first in seeking out the attention of a Cardiologist. Now, perhaps, you should make and appointment with your Primary Care Physician to set up a plan of where you go from here as the problem has not dissipated.
I would call your Dr. today and see if you should be seen in person today when your having the symptoms. It is always best to rule out anything serious and if all of your neuro exams are normal than look toward Fibromyalgia or whatever your Dr. feels may be the problem.
Good luck and let us hear from you.