Teen Mom or Wait ?

I'm turning 18 in July & my boyfriend is already 18 with a job. I recently graduated high school (he hasn't yet) & he really wants to have a baby of his own. We've been together for more than a year, his household is FULL omg... I've been on birth control since forever 😂 and I don't think I'm quite ready for a child.. I mean I want to live free and spend on myself and be without a huge responsibility.. But i dont know how to persuade him to wait .. Any advice?