I've been feeling some heaviness in my chest, not so much pain but more like there's something pressed against it. It's also affecting my sleep. My left shoulder and fingers feel a bit numb too, but it's more discomfort than pain. I used to smoke occasionally, like one or two cigarettes every few months, and I drink less than three days a month. All these chest discomforts have been around for about two years now. I saw a doctor back then and they said everything was fine, but it got worse with numbness and lightheadedness, and they said I had spondylosis. I've also had a shoulder injury since 2009, which I didn't really take care of. I'm trying to figure out if this is heart-related, gastric problems, or something due to my shoulder injury. It's really starting to affect me a lot. What could be causing these issues?