You do not mention a family history
of heart disease or problems
of blood pressure or obesity. Taken in the context
of your
youth and the number of tests you have already had, then the lightheadedness, shortness of breath, and the kind of chest pain you describe are absolutely *not* diagnostic hallmarks of heart disease for you. They are, however, characteristic of anxiety.
By all means, see a cardiologist. But if he/she tells you that you're OK in the heart department, you are.