Just wanted to report that the following day I took the same dose, and had a similar but much less extreme reaction. Since then I've gradually worked up to the full 1000mcg dose and feel a bit jumpy/edgy/energized, but nothing like that first day.

I still tend to get very tired a few hours after taking it.

Guess my body really needed it that day, or just needed to get used to the methyl and the dosage?