I slept with a minor who lied about his age

When I was 21 I was at a house party where most of the people were 18-21 and long story short, I talked to and ended up sleeping with this guy(I’ll call him Brett) who said he was 19. About a month later, one of Brett’s friends had added me on Snapchat asking me to hang out and hinted at wanting to hook up, I asked him if he was only reaching out because of what happened with Brett and he had no idea it happened, and informed me that he had JUST TURNED 17. I’m 29 now, and looking back I just feel so gross about it. I haven’t told anyone because it’s just embarrassing. To make it even worse, my sister in law who is 3 years younger her than me, went to school with him and has also slept with him. Small world, I guess?? 😅