Yep, that's a swollen lymph node, which usually signifies there's an infection or foreign body of some sort that your body is trying to fight off. If you have any other symptoms such as a fever >103, chills, sore throat, cough, chest pain, or other signs of sickness, I would get in to see a doctor or community care center. You may need to have a CBC and blood culture drawn to detect infection. However, sometimes your body can fight off infection alone so treating symptoms may be the best thing at this point (treat fever with Tylenol and runny nose with antihistamine, etc.) and if you're not better in 7-10 days or your symtoms worsen after 3 days, you can go in for antibiotics.
__________________
Please let me know if you have any other questions or need clarification. If you are satisfied with my answer, don't forget to hit the green ACCEPT button! Bonuses greatly appreciated! Thank you for your confidence!