33 f , healthy bmi, non smoker/drinker, sedentary, normal blood pressure

I have been to a heart specialist twice and they never picked up anything weird.
I have had heart symptoms for almost 1.5 years now. (every second of every day)

I found out last May that I can drastically halt the symptoms if i NEVER raise my heart beat. This means I've had literally NO exercise for 5 months.

If i accidentally raise my heart rate due to a surprise, fear, or even just picking something heavy up- the symptoms will flare up.

The symptoms are big enough to be picked up on a heart beat detection app.

Physically i feel chest pain and discomfort, and i can feel my heart beating in a twitching or too strong manner. my limbs get tingly/pins and needles easily, i get headaches, a bulge in my right neck vein, out of breath, pressure on my back, hot flushes or feel dizzy/weak.

The app picks up no s1, a mild mid systolic sound and then a double or even TRIPLE s2 that is very loud. It's most noticeable when my HR is at rest, if i have been walking around it might be able to pick up a soft s1.

Test ran were ECG, stress echo, echo, 1 month halter, 24 halter. Nothing was overly concerning to them.

So I have told myself 'it's anxiety' and tried to moved on - it's been easier and less stressful since I realized the hack of never raising my heart rate - but this is impractical in life and also very unhealthy.

When i do have a flare up from even a few seconds of raised heart my heart beats 'wrong' for days and days. up to a week. I hate it. It really DOESN'T feel like anxiety to me and I don't even feel anxious...

Any advice on what to do, is there another test they haven't done which might reveal something?

I also have nerve issues on my left side which was thinking might be effecting my heart maybe? Vagus nerve stuff?