What can I do to decrease this pain, knowing that cough syrups don't work miracles?

To diminish the pain, you can try using nasal hygiene with a saline solution like Hydrasense or Sinus Rinse. This can be done as often as needed throughout the day and at least 30 minutes before bed. Drinking plenty of fluids, whether cold or hot, can also help. Using throat lozenges like Halls or Fisherman's Friend can provide relief for throat irritation. If the pain persists for more than 7 days without improvement, it's advisable to see a doctor.