Good for a first try; you seem to have a basic idea of how to draw clothes and hair. However, in your first doll, the clothes seem to be block coloured with only a small amount of shading, and in the other dolls, particularly the first and second examples, the clothes are pillow shaded. You're trying to strand the hair, which is good, but you need to do a lot more shading than you have done. A good tut for beginner handdrawers can be found at
Ninique's Minidollz which will teach you the rudiments of shading, choosing pallettes and more.
Watermelon Bubblegum also has some great tuts, including a full doll tut.