Hi, Mandy . . . your larynx (voice box) in your throat can become irritated and inflamed from sinus drainage due to allergies or a cold. The usual symptoms are discomfort in your throat and sometimes having difficulty speaking.
I had it so bad once when I was young that I could not talk above a whisper. It should resolve itself in a few days with treatment for allergy or cold, but if you have no other allergy or cold symptoms and it does not go away, see your doctor.
Drinking warm fluids such as tea will help and making sure the air where you are is not too dry with a humidifier if need be.