Sent nudes and scared

Listen,sending nudes is not normal and this kind of behaviour is very slutty.Don't you girls these days have any self respect or dignity left at all ?Who told you sending nudes to strangers was a good idea?Are you not aware of the dire consequences associated with sending nudes?What if they expose your pictures on the internet?
Youth of this generation SMH...

A few months ago I would speak to guys on Tinder. Because I'm the complete opposite of a slut in real life I guess it was fun to be a bit of one online. Guys would ask for my Snapchat so I sometimes gave it exchanging nudes. I sexted a few guys and afterwards would feel really bad and block them on Tinder and Snapchat. It wasn't until one screenshotted a photo of my boobs that I have never done it again. He said he deleted it and I went mental making him prove he deleted it. I never had my face in them except for cleavage shots /maybe bra out a bit but they were of me masturbating. I just got a snapchat from a random account asking me sexting questions. I asked him how he got my username etc and eventually he said it was on a 'slut snap and swap' list on Facebook. He asked how old I was, I lied, and he responded that he knew I was lying and my real age (I'm 20). He said he didn't know what I looked like but he said 'beautiful' so it makes me think he's lying. I'm so scared I realise it was SUCH a stupid thing to have done and I haven't sexted since that screenshot. I only ever sent nudes on snapchat to people and no one screenshotted besides that particular man, but I know there are snapchat digging apps to get the photos back. I did send some videos of me masturbating on snapchat but now I'm so paranoid and I don't know what to do. I've tried searching my name in google and nothing comes up. I don't know if its just coincidence that my name was on that site or its because of the Tinder thing, like one of the guys on there put my name on the site. Also my snapchat username as well as my age were in my IG bio (now removed) so I don't know if he got it from that and is lying? He kept asking what i was wearing etc and i said leave me alone. He said he wanted to know who he was talking to but he said beautiful and I'm so frightened he knew what I looked like (I didn't send him pics this was on the messaging part) and he kept calling me a liar. I don't even mind so much if its just my username and age in the list, but if there is a photo I really don't know what to do. I'm scared people can see my pictures all over the internet and i don't know about it. I feel sick and I can't believe this is happening, I was so stupid and naive. Am I overreacting? I wouldn't be scared as Ive not sent nudes directly to people away from snapchat, but what if on the list they used one of my tinder photos? Please help I feel sick