I've read quite a few posts on this SE, but I would like some specific feedback to my situation.
I've been working at this company as a software developer intern for over a year. I'm a full time college student and will be graduating come this December.
Just a week ago, I had a performance review with my manager. She said she was very impressed with how quickly I was able to learn, had great feedback from my peers and my project manager, and my feedback in meetings and code reviews were helpful. She gave me a bonus and I asked her if she would be willing to hire me when I graduate - she said yes, because of the aforementioned reasons.
However, just yesterday, I had a quickly scheduled performance review with the same manager. When I was walking down the hall talking to one of my co-workers, I used a curse word. I wasn't aware of how loud I had said it, but more than one person heard. I guess that somebody very important had noticed and told my manager - she said she was letting me go, citing professionalism and that she's never had to have that conversation with others before.
She offered to let me stay for the next month until my co-worker and I are finished with the application, or leave immediately. I chose to stay as 1) I need the money, 2) I need some time to find more opportunities, and 3) I'd like to finish the first real production application that I've helped create, and I could show it off in later interviews.
I'm very saddened as things were going great. I'm working to get some endorsements from my peers and connect with them on LinkedIn currently. My biggest concern is how do I address this in an interview if asked why I left the job? Is saying something like "I was told I was performing well, but I said something inappropriate. I regret it and will now keep that kind of conversation outside of the workplace" not the best way to describe the reason? I feel like I can describe so many positives about myself, but I fear this one negative will haunt me forever.
I wish to finish the last month strong. Are there tips on getting endorsements/what to ask for when asking for recommendations, and how to word the reason for being fired in an interview and job application?