Is it wrong I’m mad?

So I went with my bf to his dr appt & it’s a new drs so they obviously ask questions to get to know him. So the dr asked him “how many kids do you have” he says just one. (He already has a son 6 yrs old) so knowing I’m pregnant I kind of felt some type of way about it & when the dr left I was like uhm you pretty much have 2 now but ok. And he says “it’s not here so no I don’t have 2 kids I only have 1 it’s not considered a kid or my kid till it’s here” so he got mad because I got into an argument over it. Did I over react for no reason or?