Russell A. Sassack, D.D.S.
If you wait for 5-7 days, and there is no improvement in symptoms, this could be a sign that your nerve is not going to heal or "settle down". Given that the only alternative is root canal treatment, we often encourage patients to wait 2-3 weeks if they can manage it to give a proper amount of time for nerve healing.
Post-filling symptoms are due to inflammation and so NSAID medications (such as ibuprofen) tend to be superior in providing comfort when compared to Tylenol. Of course, you'll want to make sure that you can safely take NSAIDs like Ibuprofen first.