Aggressive Chihuahua

Question
3 weeks ago my mom's boss gave her a 5 month old chihuahua(hairy coat). We have tried to train him, teach him basic commands,etc. He usually sleeps in my room on the floor on his bed. Last night he wanted to go outof the bedroom but I ignored him.I hit him with my pillow few times to get him to go on his pillow, 2 minutes after he got really aggressive and started barking non stop. I shouted stop and then finally I ignored him. What do I do in this case when a dog is aggressive and tries to attack his owner?

Answer
First of all, think what you must look like to a tiny little dog like that.  To get a better idea, get down on the floor and check things out from his level.  Then, imagine that a giant is after you, and trying to swat you.  Even though a pillow seems harmless to us, to a Chihuahua, it might seem as if you were the "attacker".  So, when dogs feel attacked, they do one of two things - they cower or run away, or they bark, growl, or bite.  I would suggest that you take some training classes with this dog, since it is pretty apparent to me that you need some education in dog behavior, and he needs some education in how to live successfully with humans.  I like to look at it as a "language barrier" that you can learn to bridge.  If you can, get a copy of Jean Donaldson's book, "The Culture Clash".  Some libraries carry a copy, but you can get your own at dogwise.com.  Another good book for Chi owners is "Little Dogs - Training Your Pint Sized Companion" by Deborah Wood.  There are some free lessons at www.clickerlessons.com.  Check it out - clicker training is fun, and most dogs do really well with it.  Plus, you aren't "correcting" your dog all the time - instead, with that method, you teach your dog what TO do, instead of the bad behavior.  For example, wouldn't it have been cool, instead of swatting with a pillow, which scared him, to be able to just say "go to your mat" and have him do it?
Hope this helps.