I'm going to start by saying that it looks good. It honestly does.

Now i'm going to tell you what to fix:
1) Get rid of the reflection under the title. it looks unrealistic (even for a glossy reflection)
2) you might want to scale down the navigation font just slightly, and add more spacing between the links.
3) you've got a really vibrant red line on a pretty dull red background. Both are fine colors selections. However, they don't go together. Either make the background more vibrant, or bring the saturation down on the bright red lines to match the background as it is now.

Other than those little things (which are really fine tuning) you've got a really nice simple header.