Not bad, I like the atmosphere you created a lot, and the depth is pretty nice as well. I'm glad there's really no dull spots where there's nothing happening. You should've appealed to the renders light source(s) some more to help with the blending. the red blending you did around the render looks a little awkward because it's a little out of place (due to the red stuff not being anywhere else in the piece) if you made it more consistent throughout the piece I'd say it was blended well. If not, then I'd get rid of the red stuff and find a new way to blend the render in.
Also, you should add some little bit of light source on the render (in the proper spot, obviously) to show the explosion just to add a little bit more blending into the piece.
Not bad for a first Large art, those are always a *****

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