when I was a child

I have no idea what i would write. Could I tell about my experience when I was a child?
When i was a child, I liked to play under a tree. My friend and I liked to play such a cooking. we took leaves from the the branch of the trees as a money for paying something. I was taking  leaves and i shocked very much because I touched something alive, I saw it moved,it's kind of animal just like a lizard but I believed it's not a lizard. it has green color, i thought it was leaves because it's green just like a leaf. I ran quickly.
From that event i don't want to play near a tree.Do you know,what animal is it??