Are you referring to system edema (fliud build up in feet and ankles, etc.) and lung edema or pericarditis that is fluids, swelling and irritation of the pericardium, the thin sac-like membrane that surrounds your heart. Pericarditis often causes chest pain and sometimes other symptoms. Pericarditis may be acute or chronic. The sharp chest pain associated with acute pericarditis occurs when the pericardium rubs against the heart's outer layer. The system edema does not cause any pain.
Mild cases of pericarditis may improve on their own. Treatment for more-severe cases may include medications and, rarely, surgery. Early diagnosis and treatment may help to reduce the risk of long-term complications.
If you have acute pericarditis, the most common symptom is sharp, stabbing chest pain behind the breastbone or in the left side of your chest. However, some people with acute pericarditis describe their chest pain as dull, achy or pressure-like instead, and of varying intensity. The sharp pain may travel into your left shoulder and neck. It often intensifies when you lie down or inhale deeply. Sitting up and leaning forward can often ease the pain. At times, it may be DIFFICULT TO DISTIQUISH pericardial pain from the pain that occurs with a heart attack to directly answer your question.
With heart failure (blood pumped out does not meet oxygen demand), as a consequence of poor pumping ability the blood backs up and fluids leak into the lungs, and right side may be compromised as well and fluids leak into the peripherals.
You may be able to self diagnose if you have a problem or not. If you have swelling in the feet and ankles you can raise your feet when laying down and that sometimes helps (gravity). If you have lung edema, often there is a dry cough when laying down. For me, it felt as if I were choking, drowning sensation, and I hyperventilated to get enough air. Sitting up resolved the immediate problem, but a day later in ER it was determined I was in heart failure mode..