I had 2 rct 4wks ago & still having pain. nothing seen on cbct or 2d xray. dentist said its gum pain mimicing the pain. is that possible on rc teeth?

Possible: Is the pain getting better, worse, or staying the same over time? Pain when you bite down, throbbing pain when you lie down, or pain all the time? Do meds like Tylenol alleviate the pain? If the tooth was really infected it can take quite some time for the bone to heal (even up to 6 months). If the pain is the same or getting worse, it's best to ge a second opinion from an endodontist.