There are several possible conditions that could be affecting your kitty. One of the most common problems that causes these types of signs is a tooth infection. If your cat has not had regular dental care, plaque and tartar build up on the tooth and invade the gumline, causing a bacterial infection, and/or abscess. It is not uncommon for an animal with dental problems to require one or more tooth extractions in order to alleviate the problem. With the age of your kitty, this could be a definite possibility.
As you are also observing possible tongue problems, I would also not rule out the possibility of either a laceration-type injury, or a particular type of tumor within her mouth/gums or on the tongue itself. A common type of tumor seen in the mouths of cats is called squamous cell carcinoma. This is a cancerous type of growth that can grow rapidly. It is often treatable, however, so don't hit the panic button yet!
Other possibilities to explain this behavior, though not as likely would be a jaw fracture, a foreign body lodged in the tongue or mouth/gumline, or perhaps an abnormally large of infected salivary gland.
Hopefully your Veterinarian will diagnose some tooth problems that can be easily remedied with some dental work. I'm glad you're taking your friend to her vet, as this certainly sounds like something that needs to be addressed!
I hope this has helped, and please let me know if I can be of any further hellp.
Thank you, XXXXX XXXXX of luck to you and your kitty!