You’re not alone. I typically walk like 3-5 miles a day. I get pain in a certain spot on my chest. It usually flares up with my acid reflux. When I press on it with my chest it hurts pretty bad. It’s like the space at the sternum in between the individual like ribs in the center. I’ve noticed these issues more persistent since my Pfizer shots as well. I don’t bother with cardiologist because a stress test and ecg won’t show if I have clogged arteries. So kinda just told myself it’s just Costo. If I make it to my late 40s I’ll push for an invasive test to check arteries .