40–49cm Dolls First doll...! 1/4 Mature Female w/Elf Ears

She looks awesome so far! It might be nice to add a little more detail to her upper lip, which you could carve in. Although I might wait til you have nicer clay before you put too much work into this one, because I once made a really cool head only for it to completely fall apart because of cheap clay. Good luck!!!!! Doll making is a blast

 

i love her little nose! X3
she looks pretty good, for coming from someone with no sculpting experience. i could wheedle away at all the tiny little things you could do to this head to improve it, but i am sure you have thought of all of those things yourself. haha. however! it would greatly behoove you to get at least a couple of sculpting tools.
http://www.dollmore.net/shop/step1.php?number=13355&b_code=B20050603012757&c_code=C20050607065830
this is for a lovely little set of the standard clay sculpting tools. the one i use the very most for any kind of sculpting is a combination of the first and last ones pictured. that curved sharp spade thingum is the best thing for doing any kind of tiny detail work, smoothing out seams of bits of clay added to your main piece, poking holes, etc.
the dagger-like triangular one is best for cutting little bits of clay.
and, of course, having those two little pin-points and the two lovely little rounded thingums are icing on the sculpting cake.
also, i don't know how big your doll's eyes will be, but i recommend getting the correct size "reamer" or "beveler". you can find the bevelers on dollmore as well, but the ones i have used are wooden, and can be found everywhere on ebay: http://www.ebay.com/itm/Doll-Eye-Si...381318?hash=item1a1b40cd06:g:FAgAAOSwD2pXFlgu
that link is to a nice full set, with most of the sizes that people use for eyes. you use them when the head is wet, so the eyelid and everything is formed on top of it (it stands in for the plastic or glass eyes you will be using) or, you can do what i did, and wait until your head is dry, then take a bit of wet clay and smoosh it into the inside of the eye using the tool...
BUT ANYWAY this is fairly good for a new doll adventurer! can't wait to see the rest of her forming.

 

Your sketch is very pretty. You may want to take a second look at the shoulder joints, though, because as they are drawn it seems like the arms would not be able to go any lower than the position that the doll is drawn in. To be able to hold the arms straight down, either the shoulders would have to be wider, or the chest narrower. Or you could work around it by the shaping of the upper arm.

Sculpting tools are nice to have, but you do not necessarily need to buy them ready made. Anything that happens to have the right shape works. I often find myself simply look around on my worktable for whatever I need just at the moment. Some of my reoccurring favorites are common toothpicks, drinking straws and a few wooden dowels roughly carved into the shape I needed at the time. A sharp, thin blade is nice to have as well.

I usually find some sort of place holder for the eyes to sculpt around, a pair of glass marbles or wooden balls in the right size or similar.
If you make a more carefully shaped core next time, consider to partly imbed the placeholder eyes into it and fix them in place. That makes keeping things symmetrical a bit easier and can help to keep proportions more consistent with your sketch.
As it is, the eyes seem to be too high up towards the forehead on your sculpture, while on the sketch they look great.

 

I found I didn't have tools around besides wood carving tools- those are more helpful for carving dry clay than sculpting. I bought a few cheap sets with tools I thought I could use, then added any specifics as I went along.

I think her head is much too short, you are right- build more onto the top of the head. It may help you to look at a basic anatomy of the head/face chart, even if it causes you to deviate from your plans slightly.

A good place to start, especially if you find realistic or photo reference to be too distant from your vision is the "planes of the face" which help build form and surface planes to better emphasize a 3D

Google search: planes of the face

Various age proportion chart / Jeff Searle

For the eyes if you want to go more in the inset direction this image may be helpful too: Google images link to image on facial folds by anatomy 4 sculptors (now anatomyNext)