Would you have called the police in this situation?

I was standing in my living room looking out my window when an SUV pulled into my yard. A woman jumped out and ran to the back and yanked a kid out and started punching him with her fist. He was anywhere from 5 to 7 years of age. He was so stunned or scared that he didn’t even cry. I grabbed the phone and called 911 and ran outside yelling at her to stop that I was calling the police. She was so crazed I don’t think she heard me. I said it over and over and finally she looked at me and said “call the police, I don’t care.” I did report her and I did have her license number. She threw the kid back in the car, didn’t buckle him in and took off.
Did I do the right thing?