Severe pain following root canals, has happened to 4 teeth. No infections present, nothing shows on xrays. Has been several years on lyrica and cymbalta with no explanation or improvement. After root canal I got pain from procedure for a week, no pain 5 days, then rapidly escalated to 7 to nine level. Had 2 root canals years ago , no problem. Only difference is I now have chronic Lyme and Chronic fatigue/fibromyalgia. Seen doctors, dentists... any ideas?