Defamation: I Am Being Blackmailed Online

Im not sure if this is the right forum for this but here it goes. I was on a social media app when I was contacted from this guy who said his friend wanted to meet me. His "friend" was a very attractive young lady so of course it caught my interest. I agreed to meet but when I got there it was only the guy. He said that if I did not let him perform oral sex on me he would post some nude pics I had sent through kik messenger to what I thought was the girl in the photos he sent me. Not only Terrified of my friends and family seeing these photos, I knew the man owned a handgun from photos he had on his page and was afraid for my life, so I did the stupidest thing of my life and agreed to let him perform oral sex on me. I felt so ashamed. Now a year or so later he sends me a video of him performing oral sex on me and says that if I do not have sex with him he will send the video and texts to my friends and family and post them on a shaming website like thedirty.com. He said that if I have sex with him he will delete everything and I'll never hear from him again witch I don't believe for a second. Isn't this blackmail and defamation? Is there anything legally I can do? I would prefer to scare him off with some legal facts so that I don't have to actually take this to court and have the embarrassment of my friends and family finding out. Please help ASAP

Defamation: I Am Being Blackmailed Online