You may want to go back to a dentist. After having a root canal done (I've had a few, experienced), the initial pain had gone away but a day or so after, I started feeling pain again. An infection had managed to start up. My dentist opened my temporary filling back up, rinsed the puss/infection (the reason for my pain and pressure) away, and subscribed some antibiotics. Usually the rules with oral surgery talk about no suction- don't use straws or smoke cigarettes, I had avoided both of these, but still got infected. Good luck!