Place it at the exact moment of the mishap in a short fail edit, after a Cartoon Slip to set up the fall and before a Minecraft Oof to stretch the joke, keeping the sequence tight so each reaction follows the last without a gap.
About this sound
This is a very short clip, just over half a second long, of a young child saying 'ouch' in a clear, high-pitched voice after a bump. It feels funny and a little dramatic because the small yelp sounds bigger than the hurt behind it, turning a tiny accident into a cute, over-the-top reaction that works as a quick comic beat.