i have noticed over the lasy few days something weird on the left side of my chest under my breast and upper rib section...i am not sure if its just muscular and i do notice it more when i have eaten and am full. it feels like a pain/ache right under my breast...it feels like a tightening dull ache that sometimes gets stronger when i am full...i dont think its heart related...it is almost like my chest has the feeling you get when you have a brain freeze from drinking something cold,it sounds weird but its the only way i can describe it! i have researched and read up on some things that it is common to have muscular problems in that area...i am only 36 and very inactive with progressive back problems over the last few years....