Answer
I got my tongue pierced exactly 1 week ago, and I'm going through the same thing. In fact I was online searching to see if anyone else has come across this while their tongue heals..
My guess is it's a combination of the "dead cells" collecting that I've read about, along with the fact that a tongue piercing can cause your mouth to overproduce saliva while it's trying ot heal itself. This is why you have to swallow twice as often now, and the saliva seems almost "thicker".. and coats your tongue more than usual. - At least this has been my experience. Maybe this is what's causing the "white tongue" like I have too?
ANSWER
If you have been using a lot of mouthwash or if you your has been getting dry on top, it is most likely thrush, which is a yeast infection of the mouth, try diluting your mouthwash 50/50 so it doesn't kill all the good bacteria.. also you can go to your doctor and he or she can give you a pill, a one dose treatment for yeast infections. I just went through this, in fact a took the pill a few hours ago.. but you want to get rid of it fast because it can spread down your esophagas and throat.
ei näin.