What Causes Inflamed And Sore Throat?

I have an awful sore throat, It feels inflamed only on my right side. When I touch my neck, I can feel it pulsating. I'm having trouble swallowing. I have no other symptoms and feel fine besides my throat. There is no mucus or coughing. It gets very painful to swallow unless I constantly keep it lubricated with water. It has been like like this for more than 3 days.