This realization gives me a lot of peace, anytime I venture into unfamiliar territory, and eventually embarass myself.
Maybe you get into a conversation with high level people, or you make a very fundamental mistake on something you are learning. It can feel like you should just hide under a hole, but remember, this is the cost of growth. If you want to become the person who is calm under those situations, who knows the subject at a deep level, you need to go through many, many series of them.