Place it right after the mishap is shown, then follow it with Sad Violin, or cut to Nelson's Ha-Ha! when the joke turns on the person involved. Use Oh My God Wow just before it if you want the reaction to build.
Over dit geluid
This nine-second clip features Count Dankula repeating 'Oh no, what happened? Oh no, how terrible!' in a theatrical voice full of fake shock and exaggerated dismay. It feels sarcastic and playfully insincere, like mock sympathy for a disaster that is not really a disaster at all. The line comes from Count Dankula, whose over-the-top delivery turned it into a reaction sound.