A Petty Prank Gone Awry

I'm an engineer at a startup where we work long hours to ship our product. A few weeks ago, one of my colleagues was constantly bragging about how productive he was and how much better his code was compared to everyone else's. Tired of hearing it, I thought it would be funny to play a small prank on him by adding some intentionally confusing comments in his code. The idea was to make him struggle a bit before catching the joke. However, instead of seeing it as a joke, he took it seriously and got into a heated argument with me about my work ethic and professionalism during our daily stand-up meeting. It didn't go well, and now we're both walking on eggshells around each other. Maybe I should have just kept my mouth shut and dealt with the bragging.