In my mind the first question you should be asking is why you had that much caffeine? If you normalize the values, you had approx 900mg of caffeine or about 8 cups of coffee. For a regular person, that is a lot of coffee. For people like us with mood disorders, its potentially ruinous. One of the first things I did after my dx was eliminate as much mood altering foods from my diet as I could.

Don't get me wrong, I still need coffee in the morning, but I drink 2 cups of half-caf only, so about the same caffeine content as 1 cup of regular coffee. To me its all about stability, and caffeine, alcohol, sugar, etc all destabilize, so I avoid them when possible.

As far as dosage goes, simply call your pdoc and say the new dosage has unacceptable side effects (low energy), that you don't feel manic anymore, and that you want to go back to the old dosage. I can't see your pdoc saying no to that.