Metallic smelling breath

Daisy has been tested for parasites. She finished one med for one type of parasite and now she's got meds for Giardia. I've noticed her breath has a bloody/irony odour. Is this because of the parasites? She's been to the vet a few times but I haven't mentioned it before. Should I? Is it possibly just her food? She doesn't spit up blood or poop blood or anything like that. But I can certainly detect an irony smell on her breath.

I don't think she's started teething yet though I can't be sure. But there are no cuts or anything in her mouth. I'm worried.