To elaborate on what happened. I work as a bartender and I only just started working (for almost 2 weeks now) and right from the get-go I could tell my manager wasn't friendly. She would seem passive-aggressive whenever I ask her question or would put me in new roles that wouldn't be under my job description (had to talk up about that before they stopped) and couldn't even say good morning or how are you, simply things any normal person would do. There would be times I would be seeing her but we wouldn't talk all shift. The only time she would talk to me was when she was critiquing me on my mistakes (I was still learning the ropes of the job so I took all her critiques and made sure I don't make the same mistake twice).
The majority of the time I would be behind the bar making drinks and not asking too much in case I annoyed her, whereas I would be seeing other co-workers walk off and chat among themselves, and I would even see some of them playing games.
However yesterday I made a small mistake that could dearly cost me my job.
One of my other co-workers noticed that there were some new employees and decided to be nice and introduce ourselves. We had only been there for about 2 minutes and one of my managers came up to us asking us why were not at the bar. I explained that we were just introducing ourselves to the new employees. He then said we should head back to the bar, which we did after getting the names of the new employees.
This apparently got him very mad that we didn't listen to him immediately and then proceeded to tell the senior manager that we laughed at him, ignored him and were even planning to play some games during our shift, all of that was simply not true.
We were then later sent to the senior manager’s room where we were accused of all of that and we had to clock out early. We tried to explain that we were merely just trying to introduce ourselves to our new co-workers and weren't trying to do anything that would go against the rules. She then rebutted, asking us why we hadn't notified anyone that we were leaving the bar. I then remembered that I was supposed to do that, and it was my fault for leaving everyone in the dark and proceeded to apologise for the mistake.
Mind you, however, we wouldn't leave the bar if it was just me and my co-worker running it. There were 5 other bartenders there and also there were barely any customers to serve (I'm talking about 3–5 customers) so we thought this was an acceptable time to introduce ourselves since there wasn't anything going on. But I do recognise regardless of that, I should have mentioned my whereabouts to someone before leaving, and that's why I apologised for my mistake.
However, my senior manager didn't want to hear it and clocked me out regardless of what my side of the matter was. She said she would talk to me about it later. This all happened in a span of about 5 minutes.
Before I left I went to my male manager and apologised to him if I came across as disrespectful and told him I recognised my fault for not telling him before I left the bar
Later in the night, I realised that all of the shifts I was set to have had been cancelled, and that's when I realised that they may plan to fire me for something as small as this.
What should I do in a situation like this, I have never been fired from a job before because I usually do my work and not cause trouble. Is the way my manager is going about the situation so bad that it would result in me being sent home? If someone could help me I would truly appreciate it.