Abscess has created that hole in the tissue as it was chronic and you have left it unattended. The hole is a bursting of pus discharge and it's called pathological sinus. Eventually your tooth is dead. It's more likely that this condition is going to affect your adjacent teeth and may spread via blood to other parts of the body. Before it's complicated you must work on the possibility of Root Canal Treatment without any delay.

Hello mam ,it is a periodontal abcess, you should  go for scaling  and polishing of your teeth and massage your gums.  Get an x ray done to see whether tooth is dead or vital depending on which further treatment will be decided.kindly visit dentist for clinical corelation.