I overreacted to a conversation with boyfriend, I need some advice

I’ve been dating my boyfriend for 6 months and things have been going great. We had a conversation the other night and he had asked me a question and we were talking about my past relationships and it brought up some bad emotions. I was in a borderline abusive relationship more than 6 years ago and one of the questions he asked me, I had a strong reaction to and started crying and got upset with him. Now that I’m thinking clearly, I feel bad for the way I reacted and I said sorry yesterday but I’m still feeling bad that I did that to him and I know he’s not like my abusive ex. I told him I had gone to counseling and I worked on this because i know that I have triggers and am working through this on my own.

I’m worried that he is going to break up with me now because this is too much for him to handle or he’s scared of how I reacted or worried about the way I reacted to this. I sent him a little lunch gift card today but I don’t know how I should move forward with this. I’m embarrassed now.

Is this a legit worry or fear?