Is it normal that i forgot where i was and who i was talking too

I was sitting on a bench eating lunch with some friends. All of a sudden I had this weird feeling. Then I couldn't remember where I was, how I got there, who I was talking to, what about, etc. I realized I was on a bench but didn't remember going there, I recognized my friends faces, but that was all. Later I remembered some, but it feels like not me.