This is a known phenomenon: https://www.sclhealth.org/blog/2019/06/the-real-health-benefits-of-smiling-and-laughing/ https://www.sclhealth.org/blog/2019/06/the-

This is a known phenomenon: https://www.sclhealth.org/blog/2019/06/the-real-health-benefits-of-smiling-and-laughing/ https://www.sclhealth.org/blog/2019/06/the-real-health-benef... Though, I do remember reading about a collection of studies that failed to reproduce and this was one of the hypotheses. Perhaps the difference is that you genuinely wanted to smile :)