Hi Vengfull,
Are you doing any kind of sports, running, cycling, football etc.?
If not, then running a few times a week or even start going to the gym - remember to push yourself, your body will get tired even you mind. You will sleep like a little baby again
And a little thing to keep in mind:
(That is, if you drink something with caffeine in it)
Don't drink anything containing a high amount of caffeine. As the half-life (I think it is in English) is approx. 5-7 hours.
So let us say you drink something containing 100mg of caffeine, it will take 5-7 hours before it is down to 50mg. Therefore, the 50mg will still be in your bloodstream.