As you can see this blog entry is called finding your voice, and by that I don't mean your singing voice, I mean what it is that makes your drawing/paniting/illustrations uniquely yours.
When one embarks on learning how to draw, we start off by copying a lot of stuff. Some would say this is "tracing' or some would call this "using reference" but either way, we are copying another work whether it's an illustration or a photograph, and this is completely fine. Hell, there's even a "grown up" version of this called "Masters Studies" I think that asking someone to learn a skill completely in a vacuum is a very unreasonable request. Usually a reason that we peruse learning a skill like drawing is that we're inspired by the work of someone else.
Now does this make it okay to master someone else's drawing style and market it as you?... Well, I would be inclined to say no but it might bring you a little success, but I'm also willing to bet that you wouldn't want to go down as "The Poor Man's <Blank>"
So you have to branch out and experiment with other looks and styles. Surely your a fan of more than one artist or illustrator, otherwise you're a really boring person.
I guess the way to illustrate this is to go through a journey I had. Up until I was 22, i figured that I would be a pencil and ink guy and nothing more. I figured that painting was just for those people who "get it" and I wasn't one of them. Then I came across this video of Alex Ross painting a cover:
So If you feel like you're being too derivative, just throw something different into it to see if it's something you would like to stick with your art.
Now to get back to work on this comic.