What Causes Sore Throat,headaches And Mucus Discharge?

Hi, so I have an incredibly sore throat. I mean, REALLY sore. I can barely swallow. Eating and drinking is a great chore. This started about 4-5 days ago and has only gotten worse. I also have nausea, a splitting headache, and a CONSTANT pooling of mucus in my mouth. Literally I can spit out all the mucus in my mouth (and there will be a lot) and less than a second later it's full again. Is this just a common cold? My throat has never been in such pain before.