[Dr Mohsen J. Esfahani]

Thank you for your post.

A degree of swelling can sometimes happen after root canal treatment but its better to go back to see your dentist for him to assess the tooth to make sure everything is ok.

There can be some pain after root canal treatment. The best pain killer without prescription for that sort of pain would be Ibuprfen as long as you do not have any medical contra-indications to it. If that does not work, then again you will need to see a dentist to assess the tooth and perhaps prescribe a stronger painkiller.