This morning and throughout the day have been experiencing a tightness and pulling feeling. I guess what would be considered my sternum between my breasts. A couple of times I felt as if I could not pull my shoulders back to stand up straight. If I take a deep breath it doesn t make a difference. It is not all of the time just off and on today. I have been home a couple of hours and if I lift my shoulders up to my ears or in that direction I can still feel the tightness. Maybe I have pulled something.