My toddler doesn't seem phased by the fact that she hurt me, is it concerning?

My two year old was rough housing and ended up hitting her head off my lower back. I yelled in pain and shock, as I obviously wasn't expecting it, and my lower back is extremely sensitive to injury so it caused a lot of pain. I'm actually stuck in my bed now and can't get up. My SO and I both tried to explain to her what she did and that I'm very hurt and upset by her rough housing after being told to stop multiple times.She doesn't care. She laughs when she is told that I'm in pain, and she continues to jump on me and cause more pain.Is it because I'm not crying like she would that she doesn't understand? Is it concerning she doesn't seem to care about causing any pain? How can we help her learn to react appropriately? via /r/Parenting http://ift.tt/2rbxn90