I got a terrible taste in my mouth also after I had my crowns put in. I discovered that is was due to the cement flushing out of the crown, leaving room for bacteria to get to the tooth. At the time I didn't know about the risks, and didn't go to the dentist right away. I brushed my teeth often and had to use mouthwash constantly. But nothing worked. When I finally went to the Dental tech, he said it was probably the cement that flushed out (it was a temp crown). He didn't seem too concerned, and waited another couple of weeks (total 4 wks) to put the permanant ones on. Now, after a year has gone by, I have two abscessed teeth that are probably due to bacteria getting underneath the crowns.
If I were you, I would go immediately to the dentist to see what's up. The longer you wait, the more at risk you could be.
Metalic taste in the mouth could be from a number of things, it could be the sign of toxicity to some metals and or be caused by soem medications. If yo have ruled out all that, then it could be from the crown.. if it is a ceramo-metal crown that was fabricated by non-precious metals.. many women are allergic to base metals and this could be due to that.. check your gums arround the crown see if they are redder than the other surrounding tissues.. that should give you a hint of what is going on..
Hope this helps.