Finishing

okay, so, me and my boyfriend like to fuck around more often than not. whenever we do anything, he always cums, but I never finish. I’ve told him before that I have finished just to make him happy but tbh I’ve never been NEAR to finishing when he does anything. is it just me? i want to bring it up to him and tell him what to do more but I’m afraid he’ll get offended because he’s been with other girls before and he knows what he’s doing. i just want him to be able to make me finish like I can make him. any advice on what to say or do? also I’m 18 and was a virgin before him, and he’s 19.