Bah! I am living in a timezones mess.
When I got to Europe, I was with the Brazilian timezone, so everything there was 5h in advance. Including time to sleep, what was hard in the first days.
Now that I'm back, everything is 5h later. Including time to sleep. It wouldn't be a problem if I hadn't classes at night. Unfortunately, I do.
Thanks God I'm fixing this problem... And I didn't thought it would be so hard... maybe because of all the nights I had little or no sleep in Europe.