I think your reaction was perfectly reasonable! When a 13 year old tells you what's up, you gotta quit that job, get a barbed-wire tattoo, and break it off with that lying fiance!
You get your T tested, though, bro? Gotta see if that kickboxing is paying off.
PS my sister caught my nephew spewing this kind of shit online and now he's not allowed any devices until his voice changes. I thought it a fitting punishment!