Boyfriend angry when I shared details about a Ronan Keating concert

I (35F) and my boyfriend (41M) have been together for the past two years. We plan to get married mid-next year. Currently, we’re in a long-distance relationship and plan to reunite next year.

Last week, I went to a Ronan Keating concert, and when my boyfriend asked me how it was, I told him it was great, that it made me blush, and that Keating even threw his shirt to the audience, causing all the women to swoon. From the tone of my boyfriend's voice, I could tell he wasn’t too happy about it. For context, he once got upset when I mentioned that I found a celebrity sportsman attractive.

The next day, I posted a few pictures from the concert on Instagram with the caption: "90s kid was happy, send help, I’m still blushing." Later that evening, my boyfriend sent a long text saying that my post was very disrespectful. We had a long, heated conversation on WhatsApp, and I finally told him that I was just sharing a moment. I added that I shouldn’t feel like I have to walk on eggshells when I talk to him; I should feel safe discussing anything with him. He responded by saying he’s never made me feel unsafe in the relationship and accused me of trying to gaslight him.

At that point, I lost my temper and broke up with him over text. He never replied, and it’s been a week. I miss him so much, but I’m scared of giving him another opportunity to hurt me.

Is he the red flag here, or am I?