I am happy because its Friday; I had a great speed session this morning; I will be going home soon to my absolutely gorgeous boyfriend and I am going to Edinburgh next week and will be taking part in the marathon.
I think you should have a word with your coach about this. If he/she is a good coach then I am sure they will understand how you are feeling and help you to decide what you really want to do.
I have to say I am envious of your age and the possibility that you could represent us at the 2012 Olympics. To me that would be the ultimate goal but can totally understand that 6 years is a long time.
Carry on as you are and in time there will be a point where you will wake up without too much trouble, go for a run,come back and get ready for work, do a whole day's work without feeling tired and sluggish and bounce home with so much energy you wont know what to do with it. That is how I feel anyway.