I was wondering is it normal to feel pain for four days after root canal?

Normal?: No, it's not normal but can occur. If the pain is not subsiding each day, call your dentist and let him\her know about it. You might want to do that anyway for advice. Feel better soon.

Not Uncommon: Root canal therapy involves removal of the nerve tissue within the tooth. Depending on a variety of different factors, including inflammation and infection, the nerves outside of your tooth may cause you pain until things calm down. Pain meds and/or antibiotics may be in order. Call your dentist.