Great, thanks for the information.
Swelling can occur after a root canal and if it does occur the swelling will be the worst at the 2nd or 3rd day following the root canal. It will then peak by the 3rd or 4th day and then by day 5 or so it begins to go down. A very normal response following a root canal that was infected or abscessed. The pain comes from the pressure caused by the swelling and when the swelling has peaked (reached its full extent) the pain begins to lessen but your daughter will appear swollen but will have a lot less pain. The redness comes from the pressure and is also normal.
She should be using warm salt water rinses: you can dissolve ½-teaspoon of salt in 8 ounces of water as hot as can be safely tolerated, and rinse vigorously for about 2 minutes at least every 2-3 hours.
Please do NOT put any heat on the outside of the face and elevate her head when sleeping.
It takes at least 48 hours for an antibiotic to kick in.
If the pain medications she has are not working she could also try alternating every 3-4 hours between 2 Advil (400mg) and 2 Extra Strength Tylenol (1000 mg). Please do not use this regimen if there is a history of peptic ulcer or liver disease. This regimen is equivalent to narcotics for pain control.
Your Endodontist would just tell you to wait it out because she will be ok after a few days and there is nothing he would do for her in the office unless the swelling kept on increasing which is very rare.
She should be just fine by Friday or Saturday but I do understand your concerns because I would be the wondering as well,if I was not a dentist
Hope this all makes sense to you?