[ARAM Gameplay] Katarina does damage to herself

I was playing an aram as Katarina. I looked at the death recap to see how I died, and I saw that somehow I did some damage to myself. I got this to occur twice. I am not sure how, but it was magic true damage. I am not sure if this is consistent, as you can't see damages from all sources in the death recap. I did get a screenshot so you can tell this isn't bogus. You can clearly tell I am Katarina, and you can see that assisted in my own death. Check it out.