Not too shabby for a beginner
I liked the beginning and the drums, the chords you used for your "wob" wasn't too bad, try making it more bass and less treble, makes for a more powerful feel. .
Good start and keep working dubstep takes practice with synths, basslines, drums and everything else too, it's a pretty complex genre (not to say dance, techno and every other electric music it's just pretty unique. . .)
Good beginning, I see good things in the future!
Omega
(if you wanna hear an example of a heavier bassline check out "The composer" it's by far one of my better tracks!)