I have pressure in my ears, a sore throat, and chest congestion that I can't cough up because my throat is so sore. What could this be?

Needs to be checked. It seems you have an upper respiratory infection and may be associated with bronchitis but it can only be determined after examination.So consult your family physician to find what is going on and get appropriate treatment.
Seasonal flu. It is very common viral infection. Usually the condition resolves on its own with home care. Drink water and get a good rest. If there is no improvement or sore throat is severe or lasts longer than another week, or you are getting joint pain; see your pcp for evaluation.