In The Area Of The Sternum, I Feel Pressure And

In the area of the sternum, I feel pressure and tightness. When I'm sitting it's mild. When standing a bit more and when lying down it's at its worst. I also feel like my upper back feels like a nerve or something pinching like you'd feel if you were out of alignment. I do have a dr's appointment in 3 days. Hoping it's nothing to be concerned about. This started this morning when I arose at 6 a.m.