Hi all, I got my first RCT done 10 years ago on the lower jaw left premolar and although it got infected shortly afterwards, it settled down eventually and I got it crowned. My dentist initiated my second RCT on the upper left molar number 26 this November (2015) and since then the nightmare has started! My dentist cleaned out the infection and killed the root in the first sitting, prescribed painkillers and told me to come back after a week. A few days later, I felt extreme pain in the tooth and could not sleep for 3 days! I went back to my dentist and she said it was because of a reaction to the disinfectant used to clean the canals. She prescribed augmentin antibiotic along with pain killers and told me to come back after a week. The pain reduced a bit, but it was still bothering me so I went back to her and she realized that one of the canals had not been cleaned out properly. She then recleaned the canals and the pain went away. However, the sensitivity remained. A week later, she filled the canals with gutta percha and sealed the tooth with a temporary filling. She wanted me to come back after a week for the post and core filling, but I told her that I wanted the tooth to settle down and for all the sensitivity to go away and then continue. It's been almost 2 weeks since then. The tooth sensitivity has increased and even the molar next to it is quite sensitive. Also, the tooth on which this RCT tooth is biting on in my lower jaw has become sensitive also! They are reacting to touch both with my tongue and finger! What could the problem be?