Good try! Keep it up!
I admire your effort, as animation is hard work, and I hope to see more from you in the future as you continue to improve. I hope the advice below will be helpful to you as you grow in skill:
First, I was suprised that, with all the free downloadable fonts out there, you didn't use a single one, but instead chose to write the text by hand/mouse. Using an appropriate font should be one of the first things to consider.
Second, I really enjoyed some of the transitions, such as where the eyes, then the lines, then the girl appears, as well as the light grows to turn the screen white, but many of the other scene changes were very abrupt, which made things look very unprofessional. I think if you would have even added simple fading (such as fade to and from white, blend from one scene to another, or fading to and from black) to many of those abrupt scene changes, the entire feel of the animation might have been greatly improved.
Third, the music also changed very abruptly. It's best to either find a point in the song where the music "rests", or simply fade out the music, and then start the next song.
Fourth, the tale was not clear, and had some plot holes, such as why was goku searching for the girl? How did he find out about her? Why did you say "the next day", when nothing "happened" the first day? I suggest getting the narration proof-read by someone else before you consider it complete, as this will help ensure that it is clear and coherent. Fanfiction messageboards would be a good place to do this, or if you have a mentor, he/she might be a good person to ask for help. Storylines are vital to animation. If a storyline is bad, the entire animation suffers, especially with anime, unless it is something immature like the "madness" series here on NG.
Anyway, that's all the advice I have for now. I hope that you will consider it, as I'd love to see your next flash be a great one. I think you have the potential.