Your port shows potential but needs work. Study as much as you can about portraits - lighting, angle, pose, etc. The first thing I see is a LOT of similar images: high contrast, tightly cropped B&W headshots. Seeing as your signature is blurry on many of them, it's hard to tell if your photos are out of focus or if you're just compressing your JPGs too much.
http://www.modelmayhem.com/portfolio/pi … 7#29335227
That's my favorite by far. It looks like an old Japanese brush painting.
Branch out more, try new things and keep learning.