hmm...may be red looking because of the licking...or extra "attention" your sweetie is giving that paw!

When my dog has done similar things w/her paws and coat in general...I have used a spray that helps anesthesize ( spelling?) the area and therefore may help in discouraging the extra licking etc. until you can get her to the Veterinarian. Also...did you check to make sure there isn't something sticking into her paw...or a broken claw or cut etc? This would be the first thing I'd check...then go with the spray to help keep her comfy and off the licking cycle.
Good luck!
Keep us posted as to what the Veterinarian says!
cori