This is a really great start!
- I'd probably say the head needs to be a bit more rounded?
- The ears are a little high - they should start from the bottom of the nose and end at the centre of the eye. You should also try to add the lines in the ears, but they're quite tricky to do
- The lips don't have a whole lot of definition, try to add more shading from the centre of the lips outwards with your pencil!
- The eyebrows could be a little longer towards the centre of the face, as usually eyebrows come a little further than the edge of the eye
- The nose is a bit too wide at the nostrils, just make it a little smaller next time!
- The eyes are a bit oddly shaped, try to imagine eyes as a pointed oval. Also, usually the bottom of the iris is a little higher than the lower eyelid, instead of squished inbetween the two.
- You could also add some shading to the face in general, even if its just cell shade - it adds a lot of definition to your work!
Hope I could help!