Actual harm is part of an lawsuit seeking recovery for injury to the person. You say there is a mark on your arm but you do not say you are injured, so I assume any injury is minor. Since you were not hurt, I would not recommend seeking to recover for an incident like this.
What might have happened is not part of a damages claim in a lawsuit. Thank goodness your child was not injured.
I am not licensed to practice in your state; however I would agree that without an actual injury it is not likely that you will have a meaningful recovery. However, if you may want to seek legal representation from a local attorney.
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