Can you get dry socket from a root canal?

No. By definition, a 'dry socket' is a painful condition that occurs following a tooth extraction, not a root canal.

That is not to say that you cannot have pain following a root canal. You can, particularly if the tooth was acutely infected at the time of the root canal, or if the root canal is incomplete. You should consult with the dentist who performed the procedure and follow his/her recommendations.