I have been experiencing neck pressure, occasional jaw irritation, a twitchy muscle in my chest and belching quite often. seen cardiologist and er dr.

Not sure: What do the doctors say? There is no common syndrome linking these symptoms, but they are all common in and of themselves. Jaw irritation is common with TMJ (temporomandibular joint dysfuntion), neck pressure and belching could be related to acid reflux and twitchy muscles can be due to hyperstimulation of nerve or muscle irritation. For a "second opinion", consider initiating a virtual consult.