That right, most people accept to scroll down not left-right, it's difficult to follow. So do you think it's better to reduce your logo size as InsanePL informed.
And you can find that your signature picture cause this page need to scroll left and right in order to read too.
Best Regards.
It doesn't seem very organized, with the mass logo at the top and your navigation menu sunk down on the left. A tip for your navigation: it should be accessible without scrolling left/right or up/down.