Honestly you should see a vet but since they are most likely closed right now I would go to CVS/Eckerd/Right-Aid/Walgreens ect... and pick up a bottle of sugical scrub it is blue and should have 2% Chlorhexidine Gluconate. Dilute this with water to a sky blue color and soak her for10 to 15 minutes. The water doesnt need to be deep. Do this 1 time tonight and 1 time tomorrow morning then call your vet and make and appointment and make sure that this treatment is okay with him/her before you do it again.
This treatment will help her start to heal but she still needs to see a vet ASAP.