This will sound more than strange but you need to fit yourself some "Do Nothing" time to rest your brain just like you sleep to rest your body. I have worked the evening shift for quite a while (slightly earlier than you but around the same time frame) and one thing I found very annoying is not being able to optimize and take full advantage of the time I had left in mornings or late nights to get everything done...

I was then promply suggested to take some time doing nothing. Whether it be 15 minutes, 30 minutes or an hour... You need a little down time to help you get energized to tackle down that way-too-busy schedule.

Oh... and when I mean Nothing... I MEAN NOTHING. N-O-T-H-I-N-G. (Maybe pet the Feline Forces of Entropy.)