When the spotlight’s on you, like it or not you are performing. The crowd’s eyes follow your every action, their ears hang on your every word. And while you are doing your thing, impressions are being formed. Assumptions about you are being made. Judgements are being solidified. And those could be in misalignment with what you’re about, at best, or an attack on your being at worst.
You have one of two options: you can let this affect your performance, or you can perform anyway and accept that there will be things coming at you. Take in what you need, leave what you don’t.
Is the heat from the stage lights something to melt under, or is their warmth something to grow from?