Got fired yesterday with no warning or reason

Tldr: got blindsided with being let go, venting and open to any advice.

I started in a new district this year and things were going well. 4th grade felt like an excellent fit, I felt included in the community, my kids were actually making progress, I had what every other teacher referred to as a nightmare class but I was able to make it work. I had one observation in the beginning of October that went poorly. (I didn't know I was being observed, and I was using some small group time to grade quizzes and check in with individual students.) I only found out I was even observed because I saw the document in vector.

I had no conversations about any issues otherwise, constantly encouraged admin to come in and give me feed back, and did everything I could think of to keep improving.

Yesterday, (1.5 weeks before my 90 day period was up). I got called into the office at the end of the day and told I was no longer employed with them. I went upstairs broke down my room and was escorted out. They kept the guise up all day long. They even sent a message to a parent about a child hitting their child with myself attached and said the parent can reach out to me with questions 30 minutes before they locked my account.

My gut tells me that this is because I documented in a conduct referral that administration told me to "not put any demands on the student" when I asked for admin support to check with him as he was becoming more aggressive with his peers. Unsurprisingly this didn't work because apparently telling him it is time to go to steam was too much of a demand and he hit the child mentioned above, as well as a plethroa of other issues throughout the day.

I asked what the reasoning behind the decision was and was only told I should reflect on how it got to this point. I said I can't reflect without any information to which I was told their policy is only to tell me it was not a good fit.

Everyone I worked with is shocked and I'm heart broken for these kids. I've built really strong relationships with them this year and I was proud to create a space they could be productive, have fun, and feel safe. I've had teaching positions that were bad before but this one felt like it was going so well.

Before anyone asks I let my union rep know and she's looking into it, but I'm within the 90 days probationary so I imagine I'm kinda SOL. Any ideas or advice would be appreciated. I guess it might be time for a career change.