Ok, she sits up and loves to crawl around and LOVES pulling herself up on everything she can get ahold of (especially someones leg, lol).

EVERYDAY she hits her head on purpose. She grabs ahold of something with both hands and repeatedly hits her head until she starts to cry (I try to get to her quickly, but to no avail). She loves doing it mostly in the morning and evening. In the morning in her crib she hardly cries, but at night before she goes to bed, I let her crawl around and that's when she usually cries by doing it.

I was wondering why she does it? Is it something I should have her head evaluated for, like autism or something?

She also throws herself back when she's upset. If I don't have ahold of her when she does it, she goes completely back and hits her head. It's almost like a two year old tantrum she throws, only worse, I can't reason with her yet.