How to come down from a psychological high, fast?

Ok, so I had a real busy day. I have not had any energy drinks or coffee but I am real hyped up, almost like if I were on speed or something.

I am basically too full of energy, it is 11pm, I need to be awake at 8am, and this buzz seems like it will go on forever.

How can you come down fast from a psychologically provoked energy high?