Wow- beautiful job. I noticed that there are some awkward blue pieces around his jaw area, which might need to be cleaned up, the colours are pretty amazing next to each other (the contrast between his hair and the blue background).
I love how almost every piece you do I can just imagine a specific scenario. Maybe it's my over active imagination but i just picture him turning away from everything, trying to steal away a moment of peace and quiet in his hectic life. I love your use of color here, the red used is what David Bowie is to me: passionate. (even in his most private of moments).