I just got my tongue pierced 2 days ago. Why is my tongue white? Why do my teeth!

As far as tongue I don't know, have you considered brushing (no offense, but I know some people have trouble remembering to brush). But your teeth hurt for a good reason. The tongue is the strongest muscle in the body, as well as the hardest to control. While you sleep, and even if you are a light sleeper, you tongue will be curious to the foreign object and bang it against your teeth. So all night you will be hitting your teeth with this piece of metal, or plastic if you got a plastic one. You will do this for 1 to 2 weeks before your tongue gets used to it. To prevent further damage, this is bad for your teeth, I suggest a mouth-guard. They are affordable and will help with your problem. As for the pain, depending on your tooth sensitivity, Ice or Hot water should work. Aspirin and other pain medication will not help much.

My uncle is an orthodontist

Yes it is. In fact, this happens to everyone who gets their tongues pierced. The next things you can expect are swelling of the gums, a thin layer of hair growing on your tongue, and your teeth becoming immensely rotten and eventually falling out. Just as well, you may experience bleeding of the eyeballs and genitalia while you sleep. Puss may also come out of your ears every few days. This is all normal. Remember kids, piercings will ruin your life and chances of happiness. Have fun with your hairy tongue! :D

I know people.