Sorry to hear you're feeling exhausted.
Perhaps, like many people with AS, you can be a perfectionist sometimes? Maybe you are trying too hard? Qualifications are a numbers game, to a certain extent. If you know that you're an A grade student in one particular subject, divert some of your energies elsewhere. Similarly if you know there's a particular subject which you're going to fail whatever you do, cut your losses and concentrate on something else. The most important topics are the borderline C/D grades where your hard work could make an important difference.
Also, do you tend to cycle through energy and burnout / happiness and depression? It could be that your current issues are being exacerbated by the natural cycles of your own body. I know I have one or two depressed days every month, and if I cry it all out I feel refreshed afterwards. The onset of winter probably isn't helping with this.
Try to focus your time and energy as best you can, and avoid unnecessary tangents. Get out in the sunshine and the fresh air for a short while every day, though, as this will help your mood and your concentration. If you are a hippy, co-ordinate your longest working days to coincide with the full moon. And if all else fails, when you feel overloaded, listen to Portishead or Soundgarden or Leonard Cohen or whoever makes you sad, and get it all out of your system. And keep talking to us, 'cos we're listening!
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The Sociable Hermit says:
Rock'n'Roll...