I suffered from this all my working life, which for a parish priest was a quite crippling handicap. It was like agoraphobia which is an anxiety disorder, often precipitated by the fear of having a panic attack in a setting from which there is no easy means of escape. For me that setting was a pulpit, especially a pulpit which was both elevated and restricting, where I could feel trapped and exposed in equal measure.
The sense of panic was not mitigated by the belief that the message I delivered was soul-saving truth. I learned this in my youth from the Reverend Father F W Osborn who preached as if your eternal life depended on it. It felt like that to me too as I hung on his every word, and so I could never rid myself of the feeling that someone just might be listening to me with the same intensity of expectation.