What would cause dull deep pain in the chest when lying down?

Chest pain: Not exactly sure what is causing your chest pain, but at 59yo i would recommend you have it evaluated asap by a dr. To assure it is not cardiac in origin. Good luck.

Doctor: Chest pain is cardiac until proven otherwise. Have yourself checked out right away. The fact that it happens when you lie down is a hopeful sign, but not a guarantee that it's not heart related.