I had this same taste in my mouth for a while. I even read up on it and most refer to it as a metallic taste, go figure. I didn't even know that I was pregnant then but sure enough I was. What is even more interesting to me was that I was only two weeks along and having "pg signs." I thought one had to be futher along then just two weeks, I was wrong.
I pray that you get the answer you want, soon! Good luck!