Hello,
The picture you have sent is not clear per say but the symptoms that you are talking about likely suggest an impacted wisdom tooth. Since you are 20 years old, it seems that the wisdom tooth is in the process of eruption. In case you have symptoms lile swelling, pain , decreased mouth opening then visit your nearest Oral Surgeon for the same.
Next Steps
Get an OPG done
Health Tips
Warm salt water gargle after every meal for 7 days
Avoid hot fermentation