AITA for flirting with another man while having a romantic interest at work?

Im a (25F)police officer slowly got into a romantic relationship with my (26M) partner at work. It was still in the waters and we haven't even been steady yet.

I met a gorgeous man at the gym. I was suprised how much we connected in such a short time. I tried to hold back but things escalated and we were flirting a lot and it led to him being a romantic interest of mine

After thinking about it a lot, I decided that I did want to pursue the gorgeous man at the gym more than my partner at work. I wanted to end things amicably since we would be seeing each other a lot.

So I came to his home and before I could even broach the subject he was furious.This is when I discovered he was a hothead. Beyond furious that I would go behind his back and cheat on him. But I never said we were anything serious before that.

So AITA for flirting with another man while having a romantic interest with my coworker?