I think this song is about a harsh return to reality. I suppose it could be about drugs, but I think it could be about any kind of delusion. It could be anything you've convinced yourself of, tried desperately to believe. This song is the moment when you realize that you can no longer lie to yourself anymore. It's the moment when the truth comes out and you have nowhere left to go. If you think about having your head in the clouds, then it is gravity pulling you back down to earth, to reality. That realization is harsh and confusing, which is why there is both distortion and sorrow in this song. Gravity never lets you go--the truth is inescapable. I think that "I don't pull me down" is simply expressing a sense of yearning and hopelessless. The singer doesn't want to face reality. He wants to continue living in his delusion, but gravity is pulling him down anyway. It's gravity; it's not him. It's not his fault. But gravity is relentless, and he must face the truth.