The childhood trap

Whenever someone talk about what happened to me when I was a child, I am seized by total anxiety. I don't mind people talking about it in absence of my person, but I can't stand hearing it. Still, I had a great childhood, I think... They talk about usual every-day-stuff like when I went to kinder garden and hide away from the other kids to play with the plastic animals by myself. I don't regret anything and I was not treated badly from what I remember, but every time someone talk about it or tell stories from back then I panic. It feels like the walls are closing, like a trapped animal and a really unpleasent and annoying feeling starts to grow in the back of my head. It is so stressful and it is hard to describe the feeling properly, it sort of devoures me... Slowly...

This is so strange. I hope there is some psychological explanation, because I would be happy to hear it. And no, I've never been violated in any way.