Hey,
I think you are off to a great start!
Johan gave great advice regarding getting the proportion of the head right - basically he is saying you need to check each feature of the head in relation to the other features of the head.
There are two things to note: direction, and distance - they are both important whether you draw from life or photos (or at least I think so).
Direction (or angle): ask yourself 'what is the angle of this point compared to the other points on the face?
Distance : ‘how far away is this point from the other points on the face?’
Points can mean landmarks like bottom of nose, tips of eyes, tip of mouth etc.
You can also use your pencil to ‘measure’ distance and direction.
Lastly, you might want to pick up ‘Drawing on the right side of your brain’ by Betty Edwards. Very good book and many people has benefited from it, including me.
Keep up the good work! Would like to see more coming. 