im looking to find out what this strange feeling is in my chest. quite often (just had one) i get this feeling of pressure in my chest down around my sternum. its kind of like a tire riding slowly along a flat smooth road then it slips into a hole and it takes a second or two to pop out. or maybe better to discribe it as a pressure that hits for just a second or two then gone. i can run, hike, bike ride and nothing. so i dont think its my hart i was thinking it was something with my diaphragm?? i had a chest x-ray nothing and i had been given meds for acid reflux (dont always work) any ideas??