It's not to bad, but the faces are very strange to me. You're noses look really high than normal, with the mouths being to low. The eyes are directly about 1/3 of way up the head, it should almost be flipped upside down. The face in general should be 1/2 of the head starting from the eyes down, then the rest of the head being the eyebrows up to the hair, so it's a perfect length between the two. The eyes are still at the middle of the head in proportion. Your ears seem to line up right, since they normally start from the eyebrow down towards the end of the nose.
You have to keep in mind that the mouth in generally located about an inch or so from the nose on a normal human being.
With the bottom two pictures it seems you have your mouths off to the side, which make no sense to me if they are looking in the opposite direction.
And the second one I can't understand what happened to their neck, it looks broken. :/ It seems like you draw the face, but then you just do a straight line from the neck up to the top of the head. Human heads are like Os, not Ds in shape.
I also noticed the dates on the last 2.
Not much improvement from 2004 and 2009...
Or you rarely ever draw.
They only way you can get better is to practice everyday, not just except talent to be flowing in your within a few years. You have to work hard to earn talent.
It seems like you don't really sketch, but just draw the lines, then just go with what you have. It's easier to get a feel for a face if you actually sketch it out. Faces are pointy, but soft and more round with angels upon them. And hair is more free flowing than being stiff with different width.
All I can say is practice.
I won't sugar coat what I said either.
And I could have gone on longer if you had a full body.