First time that partner is going out. What am I supposed to feel? Is this normal?

Hi! I came to this sub because i felt like i would be judged super hard for my choices etc and decisions so I hope i can get some advice or good insight here.

I am a woman and in a relationship with my boyfriend and we opened our relationship. It’s strictly for sex / hookups and not to be anything like a poly relationship where it’s a secondary partner / dates / romantic commitment etc. I’m okay with that. However we don’t have very much previous expirience with either of us doing it in practice and I just want to know if it’s normal to feel a certain way etc. At the very start when he first opened up we had different rules and it was kind of “don’t ask don’t tell” and I realized I didn’t like that. Now we tell eachother. he’s definitely much more sexual than me, and wants sexual novelty more than I do. I’m a bit more open minded than some women and I understand that particular desire. He says it doesn’t interfere with our long term goals. We are moving in together next week, im close to his family, and we are serious and committed to eachother. Hes expressed he has no desire for dates and romantic attachment either, which was something that I did not want to do when we opened.

today is the first night he’s going out. I was scared how he’d tell me or that he wouldn’t be honest with me because we’ve never done it before and it’s just a new interesting dynamic. But he told me and said he was hooking up, and when he’s done he wants to get dinner with me and wants me over afterward etc. I guess im just experiencing emotions through this new expirience and want to know if its normal or how others people expiriences went. I’m glad he too me and we are honest with eachother. I’m not worried about him being untruthful to me. I feel weird and maybe a bit….just ….not sad not happy just kind of like ….? Neutral? I’m not sure. Somehow, I guess I just don’t relate as much/ find it hard to relate that someone can have / want sexual novelty without wanting more / romantic attachment. I guess what I’m saying is do / can men genuinely expirience separating sex like this from romantic and commitment. Because I know he’s committed to me and I know that cause he’s shown me in many ways. But I guess what I’m trying to say is I have a thought in my head that when he comes back from the hookup he may feel differently about me and I’m not sure 🤔. I guess I’m just new to this and also my mind doesn’t really work the same way as his.

As I said, At the very start when he first opened up we had different rules and it was kind of don’t ask don’t tell and I realized I didn’t like that. Anyway, during this time, the day after he hooked up with somebody else, he came back to me he seemed closer to me and more affectionate. I asked him why later and he said “it won’t make sense and sounds backwards but sometimes when I do those things I feel more appreciative / affectionate / want to be closer to you” . I guess I don’t really understand it but it happened twice where I felt he was extra doting on me etc. is that normal? What is that? I guess I just don’t understand it all the way.

By the way I am okay with it I’m just I guess psychically trying to understand when I just don’t think exactly in the same way . I can’t totally understand sexual novelty seeking but I guess I just want other peoples in this realism perspective. Is it normal to feel this way emotionally?