Hello and sorry for the delay.

The sensation of pressure in your chest, neck and even head is merely due to physiological response to the slight downward spikes in blood pressure that both benign palpitation events and vagal tone can produce.

There are pressure sensors in the internal carotid arteries in your neck that signal the cardiac center of the brain when a drop in blood pressure is sensed. The reason for this automatic process is that adequate blood pressure to the brain is vital. Therefore, the quickest method by which to restore pressure is to rapidly increase cardiac force. You feel this response as very prominent pounding of the heart that can extend to any part of the body.

Pain on inspiration is associated with chest-wall pain and not the sort of characteristics associated with any type of cardiac event.

The type of palpitation disturbances that you are experiencing are being caused by the vagus nerve, which innervates many areas and basically, anytime you perform and inspirational breath it unavoidably includes action by the diaphragm. This activity is very capable of inducing the type of palpitation events you are describing. They are, in all instances, entirely benign and are incapable of inducing any type actual problem. I certainly realize how unnerving the incidents can be, but it's important and even critical for you to understand the actual nature of their cause and its inability to cause a real problem.

You'll be fine.

Best regards and Good Health