idk what to do

so there’s this guy, i’ve been friends with him for a few years and dating never worked for us, so we stayed friends. him and i are really attracted to each other and i lost my virginity to him a few days ago. i don’t want a relationship with him, but i want to be fwb, but he hasn’t talked to me a lot since then. how do i start this conversation with him? do you think he just wanted a quick fuck? is he ghosting me? heeellllpppp!!