I had a vivid dream last night that I was swimming under ground in darkness from one cavern to another trying to find an exit, and looking for air pockets where I can breathe. I made it to them every time, but barely. I was very desperate and feeling that I was going to die down there. It was so real that I woke up suddenly and in distress. For a couple of seconds, in the darkness of my room, I though I was still underground.