does my daughter have autism

My daughter is 20 months and the only word she can say is bye bye and she dont see us as mom or dad. and she cant follow commands. she is amused my opening and shutting anything. she will not go to other people and she does not like to be touched. she loves music and bubbles. she is quick to go into a tantrum and  she will bite herself and others and she will hit and kick if there is a change in something that she dont want to change. she is a very picky eater we have alot of trouble getting her to gain weight. she is only 21lbs. she doesnt interact with others much and she can careless to share with us what she is doing. she doesnt like to be loved on alot so i was wondering if this could be autism?

[Rachel Thompson, Ph.D., BCBA]

I recommend that you have your daughter seen by a professional who specializes in diagnosing autism and related disorders. Your pediatrician should be able to identify a local professional. As you may know, autism is characterized by deficits in social and language development as well as the presence of repetitive behavior/restricted interests. Whether or not your child fits this diagnostic category, I recommend that you work with local professionals to intervene as early as possible to improve her language and social behavior and decrease tantrums.

[Sally44]

As she might be showing some signs of Sensory Difficulties I would also suggest you google Sensory Integration Disorder to see if that sounds relevant.  Sensory Differences can be experienced by those on the autistic spectrum.
I would also suggest googling the name Olga Bogdashina and reading an article by her in Autism Today.  She has a book called Sensory and Perceptual Differences in Autism and Aspergers which is very useful as it has a caregivers questionnaire at the back of the book that you can complete to get a sensory profile of your child.  Our Autism Outreach Department uses this questionnaire, and we have had Olga come and give seminars to us.
I found that this book explained alot of my own son's behaviours and helped me see how I could change his environment and provide supports so that sensory issues did not cause him so many difficulties.
Typical sensory problems are appearing to be deaf, or covering their ears, or getting upset at sudden unpredictable noises eg. telephone ringing, vaccum cleaner.  Problems with touch as slight touch may hurt, or appearing not to feel pain, difficulties with clothes or socks and shoes, having to remove clothes tags, problems with brushing/cutting hair or cutting nails, problems with food tastes and textures as well as smells, problems with balance or co-ordination.  
A child can have difficulties in one sense or all of them, and it can fluctuate day to day or throughout the day.  So a child may appear deaf, cover their ears, then be seeking noise by banging things all in the same day!
You can also google DSM IV for autism and see what the clinical criteria is for diagnosing autism is.  
Your daughter is very young, so if she is assessed and needs therapies then it is more likely to have a positive effect.