When i lean my head toward my chest it feels like my chest is stretching & pinching. usually when sitting, but can when standing. is something wrong?

C/p w/ neck flexion: Depends how much you are flexing .When you flex your neck you compress the jugular and decrease venous return and can cause irritation of cervical nerve roots . I would discuss this with your doctor and consider EKG, echocardiogram , rarely could be unusual vasculature or may be cervical spondylosis.( cervical spine disease (MRI) f/u /w /doc