Embarrassed about my small breasts during intimacy

So I’m (22F) planning to be intimate with my boyfriend (22M) soon. The only thing is I’m super embarrassed about my breast size. For reference I am pretty petite in general (5’2 and around 106-107 lbs) I’m a B cup and the rest of my body is proportionate. I do have an hourglass shape but I feel like that is only a perk when I have clothes on. With no clothes on I feel like I can only focus on how flat my chest is. Idk what to do. I did tell my briefly mention this to my boyfriend through texts

Me: A little sorta off topic. As you can see I’m not… well endowed in certain areas

Him: Your regarding your petite physique? I’m very attracted to it and honestly you have great assets regardless. You’re too attractive to worry about such things.

I know he reassured me but I’m still self conscious about it. I feel like he’ll be super disappointed once he actually sees them. Any tips or advice?

EDIT: Do not dm me about this😑 anything u have to say can be said out in the open if ur not planning to be weird about it

EDIT 2: Thank you to everyone for the kind words. Social media really warped my perspective on breasts smh. I have talked to my boyfriend about it and he has once again reassured me that he likes me for not my breasts but me as a whole person as many of you have said. I wish you all a cool pillow to sleep on at night and warm blankets during the winter💕