Yes I have had plenty of dreams about self harm. One a few days ago was about when I was at youth group and asked to go to the bathroom. So I did and sat on the counter by the sinks and started using a knife to make deep cuts on my arm but then I started to bleed out and screamed so everyone came rushing in and I had to go to the hospital. But ya I believe that it is very normal to dream about it if it happens in your real life.