Melanoma in mouth of dog.

My dog has melanoma for the second time. She first got it in her mouth about two years ago. The tumor was extracted and she received the vaccine for it. She has another tumor in her mouth, which we discovered two weeks ago. This time we cannot have the tumor removed because they would have to remove part of her jaw, which would be cruel. We are giving her chemotherapy pills. We actually took her to her oncologist yesterday said that it hadn't spread and that although it appears that the tumor "sticks out more", it does not appear to have grown.

Tonight I noticed a huge bump on the side of her face that I had never seen before. Could it possibly be another tumor? Can a tumor develop or be visible overnight, since the oncologist did not see it yesterday. I highly doubt it but I just want to make sure. My parents think its just a bruise or something, which I think is probably the case but I want to be sure. I always rub her face and I have never noticed that bump. I'm positive that it had to have first shown up at most a couple of hours ago. Bumps like that creep me out when I touch them for some reason, so I am sure that I would have noticed it. Since she does not have that much time left I have been paying extremely close attention to her and would have noticed it if it had been there for longer than a couple of hours. Her face looks like she has a chicken wing bone poking the side of her mouth. Here is a picture. Here is a picture of the side of her face. http://img51.imageshack.us/img51/8649/hpim1160a.jpg

Thank you for your quick response. She is acting completely normal. Do you feel that this is a matter that would warrant immediate attention from her oncologist. She is on an anti-biotic and chemotherapy medicine. Our next appointment with the oncologist is in exactly one month from her last visit which was yesterday. The animal hospital that she goes to is open 24/7. Should I take her right now, wait until the morning, wait until her next visit? What would you recommend?

Thanks. Realistically how long could one expect an 18 year old dog to live with a second round of melanoma that can't be renewed? I know there is no definite answer but is it possible for a dog like that to make it 6 months? She still jumps on the bed and acts like a puppy; no exaggeration.

Yeah it's gonna be hard as hell. I think it would be easier, although said, if was really an old dog (yes she is old in age but when I walk her and just decides to spring home I have to sprint to keep up and I was the starting shooting guard on my high school's varsity team so I am pretty fast). This dog literally has unlimited energy. She runs around all day and never stays still. It's really hard to fathom that she doesn't have much time left. I'm 22, so she's been my little doggie since I was a little kid. Thanks a lot for all of your help and advice.