An odd thing happened last night?

Well last night before I went to bed, I listened to 40 minutes of the lucid aid music stuff and I had a banana. Then I went to bed. I had one dream that I remembered when I woke up (granted, it was like 2 am) but all I can remember right now (I didn't write it down) was that I think I was on my computer and I saw my wallpaper (My wallpaper says 'Am I Dreaming?') and then my dream self started thinking about lucid dreaming and I did a RC. But it didn't turn into a Lucid dream. So the music stuff worked to some extent, but why did it not turn into a lucid dream?

Maybe you didn't put enough thought into it. You must really question reality to have a lucid dream. Also RC's don't always work

A RC is used to confirm that it is a dream only after you realize that it might be. When you did a RC in the dream you were only thinking about lucid dreaming but didn't actually think you were in a dream. What kind of RC did you use?

About the lucid aid music...
Just because you had some success on a night that you listened to it doesn't mean it actually helped. Listening to that music makes you feel like you're doing more to become lucid. That in turn builds your confidence. That extra confidence makes it more likely you'll become lucid. You can keep listening to that music if it helps build confidence, but the last thing you want to do is attribute success to an outside source. You might accidentally become reliant on the music and feel you won't get lucid on nights that you don't listen to it.