Pulsating shortness of breath: psychological or physical?

Good evening, 😬

As the question suggests, I have these strange, short moments where my breath catches for a moment, as if my stomach is contracting or something is pressing on my breathing, so that I can't breathe for a second, and then it all goes right back on. It's hard to describe, really.

I have been struggling with generalized anxiety disorder for years, but I have actually overcome it quite well thanks to therapeutic help and have absolutely no symptoms other than occasional dizziness.

Now my question:

Could this be something physical? The doctor's lung function test showed oxygen saturation at 99%.

I've also been having lower back pain lately because of long periods of sitting and driving at work.

Thanks for the help and the many tips🙏😬