How do I know if I experienced a traumatic event?

Hi.

So Im really not sure if what happened to me qualifies as trauma. Its much more minor than other things I ve heard about. I had a medical procedure done when I was 9 where sedation was administered incorrectly. I was supposed to become paralyzed and lose memory of the surgery but I was given an inadequate amount of the memory loss drug. I felt myself becoming paralyzed and I was unable to communicate to those around me. I was terrified and hallucinating strange things. I was finally put to sleep by someone who came from somewhere I couldnt see and injected me. Years later I still remember and dream about the event. I now have to have a minor surgery that has brought all this anxiety up again. I feel helpless and I dont think I can go through with it. I cant just get over it. Whats wrong with me? Did I experience trauma? How do I move past the experience?