Am I in the wrong?

So last night me and my fiance were laying in bed and I read a post on glow about if someone offered 50k for a one time blow job would you do it. Anyway it is a hypothetical situation and I asked my fiance would you let me do that? I was laughing. He says no would you do that? I said really for 50k we could pay off our house hahaha. Then I said no I wouldnt do that. Then he tells me I am lying because I looked to the left or something and called me a whore then slept on the couch last night and still wont talk to me today. I want to bring up to him that we were joking about having a threesome with another girl and I said would you fuck her? And he goes I wouldn't if you didn't want me to. Isn't that the same thing as what he's mad about with me? I didnt get mad at him then because I know we would never do anything like that nor would I give some guy a blow job for money. I dont get it. Ive never cheated on him ever. Am I wrong for what I said?