Help I need an opinion

So I was talking to this one guy from my old high school and we were getting flirty. One thing lead to another and he was saying sexual things which I went along with. But today he asked for a 😺 pic and he sent a dick pic. At first I was like no let’s take this slow and he just kept begging so when I sent one I went on Facebook and noticed that he had blocked me. And I was like wtf so then I went on snap (we sent the pictures though there) and notice he just left it open and blocked me too. I then made sure to get screenshots of our conversations to expose him if he tried to expose me. Although he didn’t screenshot the pictures. Idk what to do since I’ve been so out of it these past few month so I’m asking for help.