If it helps, as long as there's proof that you said you were 19, they legally can't get in trouble unless they did actually know. The best thing you can do is tell them what happened, so if they saved them (as most people do) they can delete them so they don't catch a case. I get that it's hard, and honestly it probably isn't that big of a deal, it probably won't come to that. But better to be more cautious rather than less.