i think you've got a very good first draft ... few thoughts:
you're menu bar is a bit thick, given how plain it is. perhaps consider a more complex gradient, making it shorter, or adding accents above/bellow/both to the active/inactive items.
the sharp corners of the "R6" block in the middle don't match with the rounded corners of the menu and the "contact information" box. i would suggest rounding them and their related outline.
if you really want to attract the eye, you need a "violator", ie a design element that breaks the boundaries of its container. you could either have some of the abstract lines leaving the header or (my preferred idea), have the R and 6 bust the boundaries of the black containing box.
other minor items:
consider adding a very subtle vertical gradient to the black background of the R6 box
consider a soft shadow or "black glow" outside the outline of the R6 box
consider making the gradient in the center of the page a touch darker at the bottom
consider adding a soft border to the "contact information" box
consider more internal padding for the content of the "contact information" box, ie move the email addresses and phone numbers 10px-ish towards the center, matching that padding amount on the bottom
consider etched bounding flourishes on either side of the menu items in that blue of the active item or a slightly darker shade there of
There seems to be an off balance between the colors used in the header compared to the ones used below.
you have a nice start in the header but the overall feeling is not so good.
First the header: the nice colors and lines effect is good, work some more on that and have it stretched to the right to not only on the left. Try to work on the contact box because right now it's ugly, I suggest to have some opacity on that so that you can have some of the nice colors and lines effect under it and space it out a bit, give some padding on the edges.
The menu: is to big in height, and because you have only 4 items I think you should not put it there, maybe you could have the menu only in text, use a nice font and put it on top of the contact details and push the contact details down.
The Content: well the content ... I think you want to add some slide show there with your work. That is good but it's to big and it's centered, you didn't use your white space very good here. the 3 block of text are centered as well, not so good. figure out what you would like to show on the first page and then design it based on that content.
The footer: There is no footer, be creative with the footer, add some social icons etc.
here is a good website for inspiration : http://patterntap.com/
Thank you very much this was very helpful!