question: im 18 years old. i feel not comfortable with my left chest(heart).sometimes it pain but sometimes it not...i have tis pain since i was 14...wnt its start to pain, i just cough and it will be normal. after long time yesterday wn i was sleeping i start to pain back.and it was worst....soon after 2 to 3 min its back to normal....but until nw i feel not comfortable....can u help me?