Welcome to HCM,
After going through your history,it is good that you do not have any thing serous,most of your tests are normal, hence please do not worry at all.
Your symptoms and presentation is related to known or unknown anxiety
, or psycho somatization.
Please relax and follow treatment advised by your Physician you will certainly feel better it may take some time.
You should relax and take yoga
to over come your problem.
You do not to go for every investigation possible just let your doctor decide what is best for you.
If you feel you can always take second opinion
Please take healthy diet and lot of water and fluids.Take proper sleep.
Please take care