Should i end the relationship? and should i tell him how i feel before i do ?

so there's this guy, and to him im just a random hook up. he calls me when ever he wants just to hook up and i know im the one to blame cause i allowed it to happen. the problem is, he doesn't know he was my first time, and i really don't think he knows how much he means to me. every time were done having , he just gets up and leave and i spend days crying and feeling worthless. i;ve finally made up my mind, i wont let him have with me anymore, cause that's just making me mre attached; but should i tell him what i feel for him and that he was my first or just leave it like that. if i should tell him, i need advice on how to go about it. please, thank you !