A good start.

A huge part of what makes dubstep "dubstep" is the beat. The beat feels noticeably weak to me. The bass, however, is off to a nice start, no doubt. It's heavy and grungy like dubstep/-core should be. The beat right now seems too FL-y, if you feel me. It needs more depth.

This is your first attempt, though, but it's a great start. :) You're on the right track. Just keep trying. Listen to "professional" dubstep and see how other artists construct their songs. Part of how I improve is by imitating the styles of artists I respect, while adding my own personally flavor here and there. But that's just me. :3 Respect.