Wanted: advice on how to tell boyfriend to slow down

Kristine
My boyfriend and I have been dating for around a month but have been friends with eachother for 3 and a half years. I am 18 and he is 21 we had sex a little while ago and used protection. I like being with him and he likes being with me both in the romantic and the sexual ways. I just told my mother that we are dating and she said that was great but dont have sex because you have to much of a future to ruin with kids right now. I kinda agree with her but i also like giving my self to my boyfriend. I want to tell him that maybe we should slow down but i dont want him to think im going back to us just being friends because i love him in every way possible. If anyone could give me some advice that would help so much.