Hi sir...
Your history seems you may have deep cavity which invoves your nerve layer...
and the paining of your side gums is due to infection which may spread apiccally in to your gum region through root canal...
Get x_ray (IOPA) of invoved tooth region done...
Based on radiographic diagnosis only , treatment option can be made...
As the cavity affects your nerve layer then ROOT CANAL TREATMENT is the only option...
If your gum region around the involvexd tooth have any acute infection, then 3 days of antibiotic coverage is mandatory before doing Root canal treatment...
Next Steps
kindly visit nearby dentist for furthur management
Health Tips
Avoid self medication...