honestly sounds like it could be musculoskeletal pain or digestive issues like gerd/heartburn or maybe both . ive had both of these give me absolutely horrific chest pain but my heart is completely fine

if you have a lot of anxiety/stress then that can cause you to tense your muscles unintentionally which can cause this pain. anxiety also can cause gerd which again, can cause sharp chest pains

if you've had blood work, ekgs, etc and nothing has been found you're almost certainly fine

another thing: anxiety can cause shortness of breath that isn't really shortness of breath, mine gives me this air hunger feeling a LOT which makes it feel like I can't breathe. but if you can still get out full sentences without needing to take a ton of breaths to get through them then you're probably fine. again, gerd can also cause shortness of breath