and no, I'm pretty sure I'm not pregnant - that was my first thought too.
Had this for a few days - nasty metallic bitter taste in my mouth. Breath itself does not smell (have asked DH to check!) but the taste makes everything I eat taste foul and is also making me particularly thirsty. Am otherwise fit and well.
Strangely I started taking some multivitamin tablets and some zinc tablets at the weekend, but am 99% sure the yukky taste started before this, although I suppose it could be making it worse.
Any ideas on what this is, or what I could try to get rid of it - I've not changed anything else - diet, toothpaste etc.
Its even putting me off my cups of tea, which makes it very serious in my book. 
Thanks.