Sounds like you have post nasal drip - that would explain the nose and bad taste in your mouth. Seriously - go to the doctor and say that you think you have post nasal drip = explain the symtpoms but especially highlight the metalic taste in your mouth - its a strong symptom of something - and links in with post nasal drip
I found this article on the internet - might help explain if you check out symptoms.
My friend had really bad post nasal drip and you can get stuff of the doctor that can sort it out completely.
You can also do things at home, like sinus massage and also this thing (I tried it once - quite pleasent!) where you basically pour water down your nose, and tilt your head and the water comes out the other nostril - clearing your sinuses on the way - can't remember what its called - its on the internet somewhere!