@tngirl1 I have been where you are, and had the same tests with the same symptoms. My dad actually was a heart patient and I was afraid that would happen to me. I saw him talk himself into having the first heart attack, and he couldn't let go of stress and it took a toll.

Take a breath, and be thankful that the doctors didn't find heart disease. That is a gift. Your tests are recent, and 3 months won't change that. You don't want to have heart disease. I know you want an answer, and you can find one. There are other reasons for having chest tightness like stress. This happens to me, and it happens in a rapid response to stressful situations. You can learn to be resilient and cope with stress. Stress is a major playing in the cause of about 80% of all disease according to doctors, and it takes a toll on your body. We evolved in a way to allow stressful events to get our full attention because it was a survival mechanism, and this gets triggered by events, and our body reacts as if it was life threatening. You have a choice to move past that thinking or get trapped in it. What you think has a big impact on your health. Don't talk yourself into having a problem.

I have thoracic outlet syndrome (TOS) which makes my neck and chest muscles tight. If I am stressed by someone treating me badly, my muscles get tighter and can trigger a muscle spasm and pain into the left side of my chest. It starts with a neck spasm, and a few seconds later, causes the chest spasm. I have taken myself to the emergency room before for this, and was cleared as they only found anxiety. It's important to rule out heart disease, and then confront the causes of the stress and try to gain some resilience over them. When this happens to me, I can use my hands to stretch the muscles out and release them which stops the chest pain. I wouldn't be able to do that if it wasn't a chest wall muscle spasm. It can also happen because of moving my head to a certain position compressing nerves because of the tightness in my neck and chest. You might want to get a blood pressure cuff and take readings so you know what your normal pressure is and consult a doctor about that if yours is elevated. After a stressful event, mine can instantly shoot upward, but I've also learned how to lower the BP with deep breathing and relaxing music. Those were things I learned to do because I had to confront my fear of surgery. I was using music as therapy and measuring my blood pressure before and after the music session and I could lower my blood pressure 15 points.

Here are some suggestions I can give you.

Join the Gratitude discussion group here on Connect, and share what you are grateful for. That goes a long way toward banishing stress and fear and helping you feel valued and connected.

See a physical or massage therapist who does Myofascial Release work. This is how you can learn to physically release tight fascia and muscles in your body. It helps me a lot with TOS, and the stress causes layers of tightness that may take time to unravel. http://www.myofascialrelease.com

Get some exercise. (as long as your doctor agrees)

Volunteer somewhere doing something you like... maybe an animal shelter.. nature center...museum....

Take a soaking bath with Epsom Salts. You'll absorb magnesium through your skin which helps muscles relax.

Spend time in nature, or with anything that inspires you with art, music or creativity. All of that has a calming effect. We have an "Art for Healing" discussion here on Connect too.

Work out the reasons that you have a stress reaction in your life. You can do that by writing journals, listening to Ted Talks, a counselor, asking yourself why you feel like you do... and is there another way to think about the problem instead?

I would also recommend the books by Dr. Sood, a Mayo physician with a mind body practice. I didn't have these when I was going through my anxiety before my surgery, but reading them explained why my methods worked to overcome my fear and anxiety. I had spine surgery at Mayo. I was afraid of having major surgery, and also afraid of not having the surgery because of the disability that would have happened to me because of spinal cord compression, and I decided that fear would not make that choice for me. I had to find a way to overcome it and I did.
Here is my story. https://sharing.mayoclinic.org/2019/01/09/using-the-art-of-medicine-to-overcome-fear-of-surgery/

I think you can go to Mayo and take a course in Resiliency and these are the books that are used. I recommend them and you'll find way to cope and think differently instead of letting stress take over.
https://marketplace.mayoclinic.com/shop/healthy-lifestyle/book/mayo-clinic-stress-management-combo_752700