We’ve been together a year and now he says maybe we’re not right for each other..

Just because I want kids in the next 4-5 years, I’m 21 he’s 22!! He expects me to wait until 28/30 years old!! And I’ve told him I don’t want to wait that long because your chances go down when you get to 30/35. Like we’ve had no other problems other than this, we’ve been a happy couple with a healthy relationship, like I always go on about having kids In The future and he gets mad at me when I talk about it, and I’m like what’s wrong with talking about our future. I just don’t even know what to say or do I’m really hurt and sad right now coz I’m getting a vibe that he doesn’t really wanna be with me, after 13 months together. any advice ?