Sometimes I catch myself doing too much thinking about my writing. Of course I need to think about the character's goals, obstacles and what needs to happen to help the plot hang together. But sometimes I can get hung up on these things instead of actually writing.
It reminds me of how I can park my van perfectly if I pull into the spot and don't think much about it, but if I pause and wonder if I'm coming in at the right angle, I start having doubts. Sometimes I even end up driving right past a perfectly good spot because I thought too much about the mechanics of the process.
Does this ever happen to you? I get fixated on how a scene will fit into the overall storyline, instead of just writing it and deciding that later. Not everything needs to be worked out. For me, a lot of the good stuff emerges while I'm writing.