thanx for sharing your concern,
is most commonly from an erupting wisdom tooth.
sometimes due to lack of space in the jaw, your wisdom molar is not able to erupt, it pushes the adjacent tissues which results in pain and pressure also due to in adequate space, it takes alternate pathway (horinzontaly , mesioangular, distuangular).
Pain may or may not be associated with swelling, in order to treat this condition you will have to see your dentist
preferably oral surgeon.
Pain killers will not be of much help in this case.
meanwhile do warm saline rinses, mild pain killer every six hours only, antibacterial mouth rinse.
As this area is difficult to clean , there are more chances of infection due to food lodgement.
So i suggest you to maintain good oral hygiene
, keep the area clean by brushing ,flossing and mouth rinsing to prevent infection.
For pain relief you can start with Aceclofenac serratiopeptidase
2 times daily .
Get an OPG radiograph done , which will show the position of tooth in relation to jaw bone and adjacent teeth, if it is impacted surgical removal of tooth will be appreciated the most.
i hope this helps,