Why is my tongue orange?

I had a bad sore throat over a week ago that turned into a sinus infection and was given a prescription for the Z-pack antibiotics.  The day after my last dose I noticed my tongue was orange.  I went to the pharmacist and she said it could be a form of a yeast infection and to try yogurt,  but to call the doctor.  Since it was the weekend, I started with the yogurt.  I got the large plaint yogurt and ate it all within 2 days and my tongue was better, however, it is still with me.  I still have a drip in the back of my throat which is driving me crazy.  I called the doctor today and his nurse called me and said he never heard of such a thing, but they will get back with me.  I don't know if this has anything to do with it or not, but I do have a fingernail that is white and coming off the nailbed, which I would think is a fungus.  I am also wondering if it has anything to do with the liver?  I am otherwise very healthy and am on no medications and eat nothing unusual or different.  I am drinking more cranberry juice now, and still eating the yogurt and hoping it just goes away because I don't feel like going to a GP to get blood work/liver enzymes, etc.  I can scrape it off with my toothbrush on the front of my tongue, but can't seem to get past the gagging for the back of the tongue.

[ENTMD]

This is most likely a bacterial overgrowth.  This can happen when one takes antibiotics and the character of bacteria in your body (and mouth) changes.  This will usually right itself over time.  Brushing your tongue is a good idea and can help speed along the appearance of your tongue.  As long as the tongue tissue itself isn't painful, red or swollen, this is probably just bacteria growing ON the surface and not an infection.  I suppose there could be other potential diagnoses, but given how this happened in correlation with the Z-pack, probably not.