My [27F] boyfriend [33M] physically hurt me on ?accident? during an argument

We have dated for 3 years and I never suspected anything like this would ever happen. I have a lot of trauma from a physically abusive mother, so I?m not sure if I?m overthinking it because of that or if this is actually something to worry about. We were kind of arguing and he grabbed my hand and squeezed it super hard and twisted it to the point that I could feel the bones in my hands compressing. My hand is fine but it got red and swollen for a bit afterward. He says he didn?t realize how hard he squeezed and that it was an accident and that it?ll never happen again. I just can?t stop thinking about it. I can?t stop feeling like I?m not safe around him anymore. My mom would do things like that to me growing up when she was mad and it was honestly so triggering and scary when he did that. I want to forgive him but I had a panic attack afterward and can?t stop thinking about it. It?s important to me to feel safe with my partner and I feel like he crossed a serious boundary.
TL;DR should I believe that it?ll never happen again? Am I overreacting? Could it have just been an accident?


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