I am not nice!

So, as we were talking to M last night, Z told her that she thought that she was really, really nice. Just to see what reaction I would get, I asked if she thought that I was nice. she was quick to answer, "no". Then she thought about about it a little more and she said that I "was a little nice." It with what she said the other day. She told me that I was mean. Ironically I was being nice at that moment. So when I asked her if she actually thought that I was mean, she said "no, but you say all the time that you are a mean Dad."