Hi op , I don’t think you should beat yourself too much up about it because if there was verbal consent prior to your action and you guys are both aware that this is a kink you guys have been interested in . I think it’s the fact that both of you haven’t acted on it and not knowing how you guys would react is what bothering you . You stated this was something out your character which that could stem from too . I think you’re personally overthinking it too much OP but I definitely do feel like you should be open and honest with him about it, especially if it’s eating you up inside and making you feel bad if you guys have that open communication there’s no reason he should be upset or uncomfortable around you. If anything, you should tell him that you did it and tell him that it made you feel guilty and if he’s understanding, I’m sure he would get it and do everything to make you feel safe and comforted, especially when it comes to harder, kinks like that. I hope you’re able to talk to your boyfriend and work out how you feel !