The story
An imitation of the streamer and TikTok content creator RupeeRicch, who in a loose sense "coined" the phrase intentionally, but as part of a pattern of comedically adding -ing (plural -ings) to various English words while performing an exaggeration of his own Indian accent. Popularized beginning in April 2026, when one of these video clips went viral and other TikTokers started using that particular utterance of the phrase as a soundbite. By surface analysis, oh shit + -ing + -s.
Etymology from Wiktionary, CC BY-SA 4.0.