Im curious about other milestones she might be behind on? Banging your head over and over is a sensory seaking deep pressure act. And lots of kids with Autsim do this. 2 of my kids have autsim and have had aweful sleep issues, and a good friend of mine her son has autsim, and she dealt with severe head banging with her son. I have 5 kids all with special needs, and in my opinion this is NOT normal. It is however difficult at times to get a dr to take your concerns seriously. If I were you I would do a simple screening through Easter Seals. It is free. And if they saw concerns they would suggest an evaluation. And since she is under the age of 3 all her services, if needed would be in your home and come to you. I hope this helps you and doesnt upset you. I just know how imperitive it is to get intervention for your children EARLY! My oldest wasnt diagnosed till he was 7 and my youngest was diagnosed at 15 mo and there is a HUGE difference! WE have been through a lot so I would be happy to answer any questions, or try to give you some ideas. Hang in there, and always always stick to your "mommy gut" :) ____@____.com