Had sex with new partner and could only think of other one whole time

New to polyamorous relationships. Started dating someone poly about 6 weeks ago and really hit it off. He told me from the start he was poly and asked if I’d be open to that before we were intimate. I said I was that I had been exploring my sexuality last two years and had dated multiple people at once but never considered myself poly since I didn’t discuss these connections with the others. Plus I was only casually dating last two years and nothing seemed to stick more than a couple of months. I knew when I met him I was going to fall for him. He’s emotionally aware, loves going deep, listens to me, wants to know me, and the sex is amazing. He’s also bi and has another male partner. All of this I was cool with. We had talked about me meeting his other male connection and I told him I wanted to. Meanwhile he kept encouraging me to date other people. Last week he dropped a surprise on me that around the same time he met me, he connected with someone else and he already introduced her to his male partner for possible 3sum. This was something we had also discussed so I was hurt. Plus he didn’t tell me about her until he had slept with her twice. He should’ve told me after the first time but didn’t. And unbeknownst to me, he slept with me after. Anyway all of this came out and I was very hurt. More because he didn’t follow his own guidelines about telling his connections who else he is sleeping with. Long story short, we talked it out and he apologized. Said he screwed up. Ok so I realize I need to keep dating because as much as I like him, he’s going to continue to look for more connections and I need to reframe my fantasy of him being my primary partner since he keeps saying he is happy solo poly and not looking for a primary partner. So I met someone yesterday and decided just to sleep with them and I feel terrible. I knew this person wasn’t really someone I want to get to know long term. I was getting hookup only vibes from him and even though I told myself I wasn’t doing that anymore I did. And I feel yucky and sad. I could only think about my other partner the whole time (who’s actually out of town this week so I haven’t seen him). I realize there is a lot to unpack here and not sure how to process it all. Also he calls his dates connections not partners so the labels are also tripping me up.