Thanks for providing more information.
Well as you describe,this lump suggests the possibility of Swollen lymph node which increase in size due to infection.
As you have sinus infection and now a insect bite(supposed to be) so both these condition can cause such swelling.
You should take OTC Claritin and Motrin for next 3 days.
Also apply OTC 1% Hydrocortisone cream mixed with Bacitracin on site of bite.
Also do saline gargles and menthol steam inhalation.
Drink warm liquids.
And you can make an appointment with your doctor on Monday for further evaluation and management.
In case you develop shortness of breath,difficulty in breathing then visit ER.
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