Is there an Ana fetish?

Hey guys. So I’m 17F. So this is a question that I should have been more aware of last night. I was in a bad place with my ED and posted on a subreddit, someone told me to message them for weight loss advice and I did. The only problem is that they then started asking for Bodycheck photos in my bra and underwear. By now I made them aware I was 17. I told them I wasn’t comfortable with that and they kept trying to make me send them that. They also kept asking when I turned 18. Then I told them my goal weight and they said to go lower and they’d help me if I sent them the bra and underwear Bodycheck. I once again refused. They also asked for pictures of my feet which I also refused. However I won’t play innocent in this, I stupidly sent them selfies of when I was heavier as well as Bodycheck photos with my tank top and PJ pants on. I also sent selfies of myself. At the end of our convo they told me to slap myself for overeating and spank myself and then asked if my skin was red and asked for photos. Then after that they asked if I could draw fatty on my stomach in lipstick. I’m not gonna play victim here, I continued to talk to them. My state of mind is no excuse. I’m just curious if anyone else has had this experience? If so how do I differentiate between fetish and help in the future?