To me it sounded more like you were trying to achieve something like one of those relaxation music things with distorted electric guitar. You do definitely need to add some variety though. Whenever I try to write something, I always make an MP3 of it and put it into my mp3 player to listen to alongside similar music. If I am not liking what I hear from my song, I know I need to change something and after listening to it a fair bit you begin to see which bits need changing. Use your favourite artists songs as a general guideline only and you may hear little things in their songs that make perfect sense to put into your song.. Then you record again and listen some more until you really start to craft the song. By doing all this, you are training yourself to do it more and more quickly each time you write something new as the entire song writing process becomes more and more natural.