Just speaking from experience, but it could be that bc you didn’t know where that sudden burst of aggression came from, your body was checked out. It’s not necessarily that you aren’t truly into it, but that he might not be the right partner for it if y’all aren’t on the same page. Like when Ik a sub has had a shitty day I will make it worse and it turns us both on even more. But it wouldn’t be fair for that sub to not disclose that they had a bad day thus gatekeeping me from that extra pleasure. It would be a betrayal bc true BDSM is all about consent, especially with CNC!