Metallic taste in mouth

I have a reoccuring weird taste in my throat and mouth and the only way to describe it is this
When sanding a car (specifically one with lead paint) you get metal dust up your nose and in your throat and it leaves a funny metallically taste. Havnt touched car in months and when I do I only do very little bit very sparadically. However about once every two weeks or so this taste just occurs in my throat and mouth. coughing can also produce this taste. Was playing netball last night and running around and all of a sudden had this taste in my mouth again.
Its an odd metallically lead taste am not around any chemicals that would cause this.
Have Fibromyalgia but doubt this is related?