I took part in a public discussion and now I'm exhausted

I took part in a public discussion and now I'm exhausted Yesterday I was one of two speakers at a public discussion and I came back with a massive headdache. It was a small event, maybe with \~20 people in the audience, but it was around 2 hours long and I talked at least half of this time, with stuttering and repetitions. I'm very happy I did it, but I know I don't feel like this after talking with a friend for the same amount of time. Do you also experience exhaustion after situation like this?