omg get that fixed asap or else BAD things will happen
A tooth that has had a proper root canal is dead. You need to see the dentist asap. Just get it checked out and you need a temporary crown on. Why don't you have a crown. You will ruin the root canal and get an infection in your jaw.... Serious!
You HAVE to see the dentist. Call them, tell them what has happened (the symptoms) and that you don't have money. Remind them of your age, and more than likely they will fix it for you and place a temp crown on it. You probably need another root canal or to pull the tooth. If you have an infection in your jaw, it's difficult and lengthy to get rid of. (I used to be a dental assistant). If you are infected, the dentist will write you a strong antibiotic. He cannot work on the tooth until the infection is gone because they cannot successfully numb you. Call tomorrow morning. Sometimes dentists work Sat. This is serious and needs to be addressed or (I think) other teeth can become infected if your jaw is infected.