First off, where's the base from? Always remember to give base credit. Secondly, shading. You haven't shaded the shirt at all, and although there isn't much you can do with such a small area, you could still have added some slight shading. The hair shading also needs to be worked on; I'd suggest adding some vertical strands in addition to the highlights.
And one minor nitpick - why are the lenses on her glasses differently shaped?
All in all, though, it's not bad for a first try
. I hope to see more dolls from you, and remember that practice makes perfect!