Funny I had a similar experience, late twenties, felt completely healthy, but was constantly having chest pains. I was a bit over weight at the time but I walked everywhere and was really active, doctors office my BP was always ~ 140/80, he prescribed me meds but I wasn't satisfied with that. I went and got a full heart study done and a 24hr blood pressure monitoring done, my heart and BP are totally fine apparently.

I really freak out about getting my blood pressure taken in a clinical setting, it's really unusual.

I had some treatment for a kidney stone recently, and after the procedure they were checking me with some pretty accurate machines, like 10 times in 24 hours (apparently), 128/80, for some reason in that specific setting I didn't freak out.

White coat HT is a weird thing.

I have frequent chest pains as well since my early 20s! They tell me it is costochondritis but my inflammatory markers are always exceptional. I know what it is now and it is totally neurological, both issues.

Wonder if you have noticed if you were neurologically sensitive to any types of foods?

Eventually they subsided, I don't even remember when, and I've never really had them since...unless I have reflux, which does happen for me occasionally.

I'm learning I just can't really do coffee / caffeine though, I don't think it's ever really been good for me, it causes reflux and anxiety for me, but I just loved coffee to much. I gave up recently however!

You might have heart burn occasionally too ?

I cut out caffeine & my chest pain completely went away & never came back.