What Causes Metallic Taste When Coughed?

When I cough I get a metallic taste. I don t have a normal sore throat. Pain and redness is localized to tissue alongside/behind my tonsil . Pain is sharp when I swallow. Feels tender when pressure is applied from the outside. Sometimes the pain radiates up to my ear. The upper lobe of the tonsil has two white pustules. The tonsil is larger than the other.Cough is getting chesty this evening.