Why do my lungs feel heavy when i try to sleep? it's like when i breathe i can hear the mucus in my chest.

Orthopnea: or positional dyspnea/breathlessness. When you are standing or sitting upright, gravity aids in lowering your diaphragm and expanding the lungs. The chest cavity is smaller when you are lying down; this may be made worse by obesity/upward pressure from abdomen. Chest heaviness may be a sign of asthma, pneumonia, bronchitis, heart disease. The "mucus" sound suggests fluid. Full eval needed