I absolutely hear what you're saying
I don't know if it would be relevant to you and your dd but my Ds is diagnosed with autism. He is absolutely like Jekyll and Hyde. Without a doubt he is the most calm, affectionate, thoughtful, caring little boy, then turns on a penny and will be punching, biting and kicking me.
Through the years we've had so far I can tell you what I've learned....
Me and our home is Ds 'safe space'. He doesn't have to tolerate, put up, or endure anything there because he is 'safe' to release how he is truly feeling.
School May be one of those places where your dd is keeping things together all day, holding/masking her emotions-but when she feels relaxed and safe she lets rip
That is totally fine. How your dd feels and acts when she is like that is fine. We all have outbursts to an extent. Your dd needs to know there is nothing to be ashamed of
We had a particular difficult time with Ds and he was extremely anxious and volatile. He has bitten staff, head butted, kicked, nipped staff.
And I'll tell you what I admire the most about my Ds. He can do these things (which btw are not something he can control at the time), and the next day he has to face those staff and start a fresh day. He apologises now on his own accord (it happens less frequently now). The resilience he has, the fact he faces these people after he's hurt them and knows he has hurt them, astounds me.
I couldn't imagine going to work the day after biting/hitting my work colleagues and just getting on with my day.
The main issue is that the adults around my Ds accept that this behaviour is not under his control currently. When he is calm he wouldn't ever hurt anyone. These outbursts are him showing he can't control the anxiety he has.
The shame and guilt he feels breaks my heart. My Ds is 8. And shame and guilt are two awful emotions to deal with even as an adult. I can't imagine how it must be for him
My point being, the staff will (or at least, should), understand that your dd behaviour wasn't personal. It was a reaction to how she was feeling. She's a child. That behaviour should be accepted and worked on so that if and when she feels like that again, she may be able to handle it better, for her.
Please don't feel bad. You are absolutely not alone x