Have really bad taste of metal in my mouth any ideas what this is?

It may be: Due to recent medications if no bleeding in the mouth and recent, otherwise that's a tough one.

Medicine?: Some medicines can cause a metallic taste. Biaxin (clarithromycin) and Metronidazole are examples, but there are others. Some may interpret certain food tastes, such as that of garlic, in the same way.

Meds vs filling: Some medications produce a side effect of metallic taste. Of course, don't over look the possibility of a metal filling.