It's over now, but looking around for something similar I think what I may have experienced is a "Dissociative Fugue".

When it first happened and I was thinking about me as "him", "his memories", it took me a few seconds to remember my actual name. When I was thinking about myself (as in the real me, not that 'Pete' identity) I called myself by the wrong name at first - an alias I used to use. I realized that was wrong and had to think about what the right name was.

I had also been thinking about going out to a park, trail, or river. Somewhere to get out and walk around. The only reason I didn't was because I knew what I was feeling wasn't quite normal, and that it wouldn't last, but I haven't been out like that for a long time. I'm glad now that I didn't do it.