Welcome to JustAnswer! I am a licensed veterinarian and would be glad to help!
Is the swelling painful or warm to the touch?
Based on the location, and if this is getting better - it could be a resolving skin infection or being a bruise or even a reaction.
But - if this does not get better, the location is also suggestive of a tooth root abscess - not the tooth itself, but an infection from the tooth root.If it does not resolve completely in 2-3 days, before the weekend It would be best to have this evaluated - especially if there is a concern it may be a tooth root infection.Always best to take care of this now, when it is small and she is feeling well - rather than later when it may be larger or she may be sick from the growth/infection._____________________________________________________________________Please click "ACCEPT" if the information I have provided has been of help so I receive credit for my work. Bonuses are always welcome and appreciated. Thank you.The above is given for information only. Although I am a licensed veterinarian, I cannot legally prescribe medicines or diagnose your pet's condition without performing a physical exam. If you have concerns about your pet I would highly advise contacting your regular veterinarian.