I'm having some weird symptoms that are really worrying me. Sometimes my stomach makes these burping sounds, and I have this cough-like feeling and a lump in my throat. My chest feels tight, mostly on the left side but sometimes on the right too, and it gets really hard to lie down comfortably. I'm getting anxious and scared that it might be a heart attack or something serious. I haven't been able to sleep well for a long time. Could you help me figure out what's going on?