greyish gums

about a day or so ago, i noticed a small cankersore on the gums above my top front teeth.  Within one day, the entire area above my gums on the left side of my mouth has turned this greyish color, and is very painful.  The texture has stayed the same, it is not bumpy or anything.  The greyish color goes all the way from where my gums meet my teeth up to the top, starting at my front left tooth and going reaching back to my molars. Also, where my top lip touches my gums in this area has also turned a greyish white color.  On top of this, my lymph nodes are extremely swollen and painful, but there is no pain in my throat.  It is so painful I have had to apply numbing gel.  i have been using hydrogen peroxide as a rinse, but don't know what else to do, or what this could be.  Please help!  

[jpark]

http://www.nlm.nih.gov/MEDLINEPLUS/ency/article/001044.htm

The information in the link above seems to correspond to your symptoms.  You better go to a dentist.