Practice makes perfection-ish
For your first animation one cannot really be too judgmental >.>...anyways Dbz and another other fighting-anime is bit overused these days...try making up your own characters and your own style of drawing(thats what so fun about being an artist!) instead of just copying someone's style.
Though stick figures are pretty awesome flash (though perhaps not make it your preference of drawing since its so...plain).
Also its good to have a storyline in any flash (though there are some rare occasions). This flash was just plain fighting, there was no rising action or climax, it was just a straight line. Pure fighting is not a story but just boring since the viewer does not really know why they are fighting or what is the importance of the fight (such as why must they fight why can't they just talk over a nice cup of tea?).
What I found pretty helpful was to first make a storyline (aka story) then plan out each scene, such as(i'll use yours for example):
Scene 1: Main character jumps off computer
Scene 2: Fight scene
etc...
but this storyline can be improved by having someone spill coffee onto the guy's computer and not apologizing, then the main character could get really mad and ask for an apology and the villain could reject, THEN they get into a fight...etc making a story isn't too difficult (don't be afraid to express yourself).
Anyways its also good to try different shots, such as longview, close-up, 3/4 shot, tilt, tracking shot, profile, birds-eye...etc :)
the more different kinds of shots you have the better your film becomes and also your audience enjoys it more.
There are tons of books, I recommend checking out how-to-do photography, how-to-do video, and perhaps even a book on writing stories. Flash videos are just like real life films only in cartoon form so the rules applying to real-life films also applies to flash :)
Anyways its always better to have 1 good apple than having 10 bruised ones (what im trying to say is that its better to have 1 good flash then having 5-10 really crappy ones)
Keep doing flash since your first flash is pretty good compare to others.
But please make your own style of art, not only is it truly fun to express your own imagination, it tells the viewer more about who you truly are (Dbz is Akira Toriyama's style, though i think you might be basing this form of style from Marti Wong's Little Fighter).