Brief Answer:
It is a normal phenomenon

Detailed Answer:
Hello Dear,
I understand your concern and embarrassment it causes to you.

First of all, you need to know that it is a normal reaction, and it's not that much rare phenomenon.

Some ways to prevent it is to overthink about it. This is a method invented by Viktor Frankl, and he says that the more you think about your stressor or the situation that may embarrass you, the less likely it is to happen. This has worked very fine with public speaking and stage performance. I think it will help you as well. It may not work directly for the first time, but you'll get better with it.

You may also search yourself for other ways of self-suggestion, and how to prepare mentally for this.

Hope I have helped,
Manoku Eni

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