Sorry I forgot to comment on how the testing was for such a young child.
First we did a hearing test and made sure she was ok in that area (which she was). Then we watched how she interacted with sound and movement. This was such an amazing thing to watch and be a part of. Ava, daddy and myself sat in a sound proof room while the lady sat on the other side of a two way mirror. She played sounds through speakers and made mechanical stuffed animals play drums. She did great at this one as well. Next we sat down with two great women who played with her and asked me questions. They tried to see if the would clap when they did, bang blocks together and activities like that. Things a child her age should be doing. This didn't go so well but definitely told us some things. After that we saw another dr who played with her, asked her things, watched eye contact, tried to get her to mimic as well as just normal every day behavior. I showed a video of the head tilt thing as she was happy that it didn't appear to be a seizure but there is something very different about what she is doing. After that she gave the results and said I would get a report in the mail sometime soon.