Get embarrassed

I would not consider myself as a shy person, as once I get to know people, I am very confident. However, I get embarrassed when in a room of people I don’t know well or leaders/decision makers in my organization. I have worked on my confidence over the last 10 years, so when it happens it’s even more of a surprise and seems even more embarrassing. Individuals who know me well are either very surprised or have used it against me to take away speaking opportunities from me. Today I got embarrassed speaking about my childhood which was nothing to be embarrassed about. I would like to increase my confidence and be able to present on the skills and tools I have that have helped me be very productive. Do you have any suggestions that would help?
Thank you,