Hi, do avoid taking any medication based on assumptions which need confirmation. You could take an intramuscular voveran injection on your deltoid muscle or glutes, immediately or before/ after dinner today and attend your Dentist appointment tomorrow at the earliest.
Also Lysoflam/signoflam to be taken orally twice daily after food in case of pain, if the need arises after taking the injection.
Next Steps
visit your dentist today if possible