should I be upset?!? he asked "who's this?" :(

Heyy, so I've been talking to a guy for around a week, we've been having sex as well too.. We added each other on snap and the other day I think he deleted me ? Cause it says add friend.. Anyways after that he still texted me "what's up" yesterday and I replied.. I didn't heard anything back so this morning  I texted him "you deleted me on snap" and he said "who's this" and I said ":( nvm" I don't know how to feel about this ? I should forget about him right ? And why could have said that??