Unidentified Chest Pain. And lie down.

Unidentified chest pain since September 2016. My chest pain is located deep in my chest, towards the right. It's not sharp but feels more like a burning sensation. It almost feels like there's a giant gaping and hollow hole there. It also feels like something is "writhing" or "rolling" around, like a contracting muscle. It is worst when I'm sitting up, and my only relief is when I am reclined (45 degrees at least) or lying down. It seems to be worse on days when I don't get enough sleep. It doesn't seem to react to food or any other factor. I have no issues breathing, exercising, or sleeping. I basically have this feeling all throughout the day, and it goes up and down. Sometimes the flare-ups are so bad that I need to stop working and lie down.