48 hr post 10 day amoxil (amoxicillin). stool runny (melted milkshake consistency) w very strong ammonia odour.bacterial overgrowth (what possible types)or c.diff?

Maybe : If the diarrhea is mild then it may be antibiotic-associated diarrhea from change in the normal flora of the GI tract. Probiotics will often help with this. If the diarrhea is severe, watery and malodorous then c diff is a possibility.

Hard to say: C. Diff infection is a possibility with any antibiotic. Given the seriousness of such an infection, i strongly advise you to see a doctor. It can be ruled out with a simple stool test.