Do I have coronary artery spasm/ variant angina?

[Jongemini]

For the past 4 months I have had intense chest pain most mornings when I awake, feeling like a crushing ache which spreads down my left arm and shoulder. It lasts up to 30 mins unless I use a triglyceral nitrate spray. I have had numerous ECGs, stress tests, heart MRI scans and CT scans of the arteries but nothing immediately obvious as the cause of the pain. It sounds like a cardiac artery spasm but wouldn’t this have been picked up on the tests? How was yours diagnosed?

What else could it be? Has anyone had similar daily morning chest pains in waking?