I get a sudden onset of pain between my shoulder blades. Pain radiates to my chest, front of neck, and I get a headache just above my eyes. When I swallow, I get a feeling of fullness in my throat. Pain unbearable at times. If I'm sleeping, it wakes me. Pain intensity comes and goes, and may last for up to an hour. What could this be? I had an X-ray done years ago, and it showed nothing.