I had a root canal 1 week ago but now my tooth is sore to the touch. is this common?

It happens: The tissues around the tooth are sore from the procedure. Were you infected? Were you taking antibiotics? Were you in pain before the root canal therapy was started? Answers to these questions would help formulate a better answer. Since the dentist treating you knows your tooth better than anyone, give them a call to discuss your discomfort.

Not very common: but certainly possible depending on where your tooth was in the spectrum of infection at the time of the root canal completion. If the trend is showing improvement, I usually tell folks to wait it out and call if it stops improving before resolution or starts to get worse. In any case it can't hurt to let the treating dentist know how you are doing and take another look. High filling may be causal

Root canal: Sometimes it takes several weeks for a tooth to be assymptomatic after root canal treatment, usually due to inflammation. Call the dentist who did the root canal treatment and let them know you are having pain. They may want to see you or prescribe anti-inflammation meds.

Call your dentist: After the root canal treatment, you may have some swelling and certainly some pain. If pain does not decrease after 1 week call your dentist immediately for post root canal evaluation and treatment if needed.