Hi in response to the above stated concerns looks like there is a cavity which requires treatment. Salt water rinsing acts as a mild disinfectant thus helping in pain relief. Without finding out the underlying cause of pain and treating it , the pain wouldnt subside. Over the counter mouthwashs do not aid in pain relief.
Next Steps
Kindly visit a dentist for a consult to find out the cause for the pain and get it treated.
Health Tips
Continue to brush twice daily , salt water rinses also will provide temporary relief.