Re: Root canal a few years ago and now have pain.
There are so many things that may have happened to your tooth. It may have started to decay under the crown. Do you hae a post in it?
You may have cracked the root. Root canaled teeth can be very brittle and fracture easily.
The only way to find out is by what you are doing. Going to the dentist to have it evaluated and cleaned. Xrays will be able to tell, for the most part, if there is decay below the crown and your dentist should be able to give you some options then.
Good luck with your appt! Please let us know how you do.
My very best to you,