How much sleep are you getting at the moment?
Doing too much can create stress which can cause fatigue, but on the other hand not having enough to do or nothing of interest to focus the mind on can also contribute.
Don't cry, don't regret and don't blame
Weak find the whip, willing find freedom
Towards the sun, carry your name
In warm hands you are given
Ask the wind for the way
Uncertainty's gone, your path will unravel
Accept all as it is and do not blame
God or the Devil
~Born to Live - Mavrik~