I think I love my FWB

We had sex one time before and I cut him off due to getting back into a relationship with my ex this was like 2017. So he have been sending messages to my sister & my mom telling them to tell me to hit him up and stuff. I never did because I had a lot going on. So I bumped into him and we exchanged numbers and we started to text. Immediately we hit off and we started talking on the phone and the chemistry was so good between us, he came over and chilled with me and we had sex . Like we literally sit on the phone and talk all day and it’s always something to talk about. We both agreed we don’t want a relationship we just having fun. But I think I’m catching feelings and I’m just curious of how he feels I’m scared to tell him and he don’t feel the same way. I want to tell him but I’m terrified of his reaction . Like we was laying down cuddling and I almost slipped and told him I love him. I know he care about me it does show and he shares personal things with me which he told me he’s comfortable with me . Idk usually I’ll fall back when I get like this because I be scared. Any advice ?