The swelling is majorly bcoz of food lodgement in the partially erupted wisdom tooth region. Wisdom tooth is called impacted when it has no place in the mouth to erupt and is blocked by bone, gums or adjacent teeth. The best solution at this point is to remove it. Trying to retain it would cause more problems in the future which can affect the next tooth as well..
Next Steps
Get the painful wisdom tooth removed and the opposing wisdom tooth as well, bcoz opposing tooth will start erupting downwards and coz swelling of opposing gums in future. So instead of getting all this procedure done again better to get it removed together.
Health Tips
Take warm saline water rinse. Avoid spicy and hard food!