I had a root canal last week top right wisdom tooth. it still hurts very badly when i chew down. there is no pain other than when i chew. this normal?

Not Unusual: The tissues around that tooth may still be inflamed. That's why it hurts when you bite down. If the pain lasts more than a few days, see your treating dentist.

Yes if high: yes it can especially if filling material is high or the tooth is cracked

Not necessarily: are you on antibiotics? do you hit that tooth first on closing? Depending upon the severity of the infection you may need antibiotic coverage. Contact the dentist who performed the procedure and discuss or revisit.

Maybe normal: Why did you get a root canal on a wisdom tooth? If you are not missing any other teeth in the arch, probably was unnecessary. Possible explanations: Tooth is cracked, which would require extraction. Infection at apex of tooth which would cause discomfort during function

Not often: 'Thee root canal is used to remove the mostly necrotic tissue and nerve from the tooth which causes pain/swelling. Depending on amount of infection, the removal of pulpal tissue plus antibiotics will resolve the problem usually within 2 weeks.. Since you are still within that time frame, it is possible residual inflammation is still present. See your dentist if problem persists beyond 2 weeks