I am now self conscious...help?!?

my boyfriend and i were discussing our pasts and we spoke about this girl who he used to be friends with and he said "oh i wanted to see her boobs" and i was like geee thanks joking around whatever. so then i was like did you wanna see mine?! still joking around and he was like yessssss and i was like howd they do. and he basically said they werent what he was expecting they look better/bigger in a bra. ive always been so self conscious about my breasts. its something that honestly kills my confidence. and hes like see this is why i cant tell you anything. so now im afraid that if i show him im hurt he'll start to go back to his old ways and be dishonest again. what do i do? im litterally crying while im typing this i need help pleaseeeee