Navigating my river of misery

One of my goal’s in Scholars is to learn to be assertive when I speak in front of an audience. I attended a big meeting today with senior managers and I was put on the spot to defend one of my projects. I was clearly in the middle of my river of misery. I flushed, had my hands shivering, and made my points in a not always clear way. I now feel terrible and want to hide somewhere, but there is a part of me that thinks that I was authentic in a way, even if my performance was not very strong. What should I do next?

Thank you for your help!