Just tell you dentist office that you are in pain and you need to be seen right away. they normally will see you if it's an emergency. anyway alot of possibility that can cause this. but a blister or a cut will appear white in the gums when its healing and pain is the soreness from the work or cut.

Get some Barkeeper's Friend. It's a powdered cleanser similar to a scouring powder but not nearly as harsh. And it does wonderful things for nearly any metal! All my cookware is stainless and I use a couple of shakes of this cleanser on it regularly to keep it shiny and new looking. It's also much less abrasive than a brillo or an sos pad. Those will leave scratches in the surface of your pans.

Just dampen the pan with water, sprinkle a little of the cleanser in the pan and give it a little scrub with a sponge. For tough stains, it's best to leave the cleanser work before you scrub for about 5 minutes.

Barkeeper's Friend is available in a lot of grocery, discount and hardware stores. And it's cheap!