Why is he ignoring me after I sent him pics?

This guy I like very much kept asking me to send him nude pics I always said no but than he asked me 2 weeks ago and I thought why not. So I sent 4-5 pics and he sent some back we were on snap chat so I'm not worried about him showing them... But anyways the next day we were snap chatting all day than out of the blue he sent me a blank pic and I said what? And he said yea and I asked him if he was mad at me and he said duh. But he wouldn't tell me why and I asked him if he was using that as an excuse to stop talking to me and he was like no no no and well haha that was the last thing he said to me.
Why is he ignoring me after I sent him pics?
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