I had severe toothache on and off for nearly a month before I went to the dentist. Turned out to be a loose filling. He replaced it with a temporary one and told me to give the nerve a chance to settle down. If I still had pain I should come back for a root canal treatment, but if no pain then return in 3-6m for a proper filling.
Thing is, I was so gaga with pain and fear that I'm not certain whether I'm meant to go back after 3m, or sooner if still in any pain. It's been just over 2w, and the pain is vastly imProved - no spontaneous pain, but I can't chew on that side.