Would I get fired for this

Basically a customer was being rude to me and stupidly I said I didn’t appreciate their attitude. I thought that was the end of it but he came back 10min later to tell me I had no right to speak to him like that and stupidity again I said I have as much a right to speak as he does. He then tells me he’s recording this conversation and going to corporate. What’s the worst that could come from this