Too young ...

So basically I have a bf and I’m 15 basically we were playing around you know at some point uh I kissed him and let him suck my nipple and I’m tryna stay abstinent from sex completely , I don’t want anything like that idk he knows I don’t want too Ik I’m too young, sometimes I get really horny as I should I’m a teen and kinda need help preventing this cause Ik being this horny is a sin and I really wanna save my virginity until marriage or I’m going to sell it I wish I could say I was joking , He never forces me to do anything I’m uncomfortable and we tend to to keep a lot of things very private , I just don’t wanna like give myself away like that I don’t know how to tell my bf without making it seem like I’m leading him on , I don’t want him to end up finding somebody else to do those things for him we trade pictures sometimes he’s never forced me to do anything I didn’t want to do should I feel guilty for letting him suck my nipples I don’t want to do any more I feel like he’s gonna think it’s a lead to sex I don’t want too feel bad so how do I have this conversation or start it , yea I really respect myself and no I’m not saying girls who loose there virginity don’t have respect , I just want to know that if I lose my virginity it’s to a man I’m going to spend the rest of my life with no shame to girls who have lost there virginity at young ages like get that dick period , please help me find advice to start that conversation and set boundaries with him! He’s not forcing me too do anything I just want to clear the air with him and he has had sex previously, I just don’t want him to think that I want too! He’s not forceful or aggressive he always ask my permission before he does things he’s not a bad guy. I mean we’ve had previous conversations it wasn’t anything heavy

UPDATE : I just had the talk with him and he didn’t seem bummed or sad he didn’t seem quite ok with it he said everything was fine I feel kinda bad because like I feel like I let him down he said “he can’t control what I want to do with my body.” Idk I feel kinda dissatisfied with his reaction ..