Is it normal to be mad at my bf for pranking me about being infertile?

Me and my boyfriend are both 19 and have been together for just over two years. Recently we’ve been talking more about kids and our future and whatnot. Obviously we are going to wait but it’s just nice to talk about it. I mentioned how i was really wanting some potatoes and he said “sometimes i reckon you’d be pregnant with the random food you want, except that won’t happen” jokingly i responded with the “what about our plans” and he dropped that he was “infertile and could never have children” he’s pulled joke things similar but not as intense in the past so i assumed it was that and told him i didn’t believe him. He came up with an elaborate but believable story with little bits of “proof” which would make sense as to how he’s infertile and things. finding out he was “infertile” made me really upset and i just felt like i’d been lied to. He said he never mentioned it to keep me happy and bc he didn’t want me to view him any differently (i never would’ve). After going back and forth he finally admitted that he wasn’t being serious and he just said it to be funny. I didn’t find it funny and i’m really pissed off with him. He said he didn’t think i’d take it so serious and doesn’t get why i’m upset. I don’t want to be dramatic but it scared me a bit and my heart kinda dropped a bit. he’s apologised and said it wasn’t meant to be hurtful but i took it really seriously. Is it the right response to continue being upset with him or should i get over myself?