Yes, I was. Not as much by adults but definitely by my peers.
Has definitely changed my approach to my DDs' schooling, compared with my parents'.
I have a lower threshold to how long I'll let kids work things out amongst themselves before contacting the school and asking them to intervene. The fact that my DDs' teachers have listened to me and have been responsive on behalf of my daughters makes me want to remain in the catchment area, even though we'd like a larger house and there are other high schools in our city with larger percentages of exam passes.
It has become more important to me that my DDs can be themselves at school, than how many kids get C or better at Higher. Didn't used to be that way, but when DD1 started primary school, my old memories of being bullied at primary really came rushing back.
I'm also more forward with my DDs' teachers and coaches if I find out something they've said has been taken too far. I'm a lot less afraid of approaching a coach, looking them in the eye, and saying, "My daughter says you said [this thing that hurt her feelings] to her. Can I ask about your perspective?"
That's actually led to a productive conversation where I can hear the coach out, and speak with DD1 later about her behavior and help her take responsibility. I've been able to explain my own background to the coach (because I also had a terrible dance teacher who belittled us all once we reached teenage years!), and the coach has been able to reassure me of her style and figure out a different and more effective way to engage with DD1.
DD would have quit her current sport without that chat. Instead, it looks like her coach understands her a little better now, and has found better-suited ways to manage her behavior when I'm not around.
I will also stick with activity teachers who know how to motivate my girls to give their best, without demeaning them. I care a lot less about turbo-achievement and trophies and "winning", and a lot more about my DDs taking joy in what they do.