Infamous "Period Sex"..by accident

So apparently my period came WAY earlier than usual. I'd just had sex with my guy. Things were great, then I get home and I'm spotting. There's no way he didn't get any on him that's for sure. How do I say "yo, aunt flow might've tried to steal the spotlight. Sorry if it looks like a massacre down there" to him without it being weird? He doesn't seem like the type to freak out, but I'm not for sure if that's something he'd be grossed out by or not.  Thanks, ladies!😘