Tired... And tired

My 12-week long industrial training programme at an architecture firm is gonna end in approximately 3 weeks. One thing that keeps bugging me is that I keep feelin' tired and sleepy at work. I know I'm never a morning person. I sleep late, I wake up late. But for the sake of adapting myself to working life, I go to bed much earlier than before. And even if I have 8 hours of sleep the previous night, my eyes keep fallin' down whenever I'm at the office. Grrr... I wonder if there's a remedy for this. Anyone?