You are the only person who truly knows if you knew what you were doing or not. (You don't have to answer to this at all, by the way.)
If you did not understand/know ... then why feel guilty?
I'd probably feel guilty no matter what, too. Yet, when you think about it, if you were truly psychotic, what choice did you have?
Before you write too much, I want to let you know that in the U.S., participation in forums online are considered "discoverable" evidence. One can be asked, under oath, for his/her screen names, forum names, etc. I just thought you'd like to know this.
It says a lot for you, in that you've been examining your conscience.

I am thrilled nobody was hurt. I hope this can be simply a loud and clear warning for you.
No harm, no foul.

WC