Short reaction phrases like this spread through meme edits, gaming clips and group chats because they say what the audience is already thinking. The awww shit line has no confirmed single source in popular culture, so its popularity comes from everyday use rather than a famous scene. Creators reuse it as a universal cue for trouble arriving, from sports bloopers to homework fails, and its brief one second length makes it easy to loop, layer over video, or send as a quick voice reaction.