I'd get retested ...
diarrhea can come from other things.

The bacteria that live with us in a beneficial way, need
to be fed something. They live down there and perform services for us in return for food.

I was watching Animal Planet yesterday about Moose. It said that the baby moose cannot eat plant material until its GI tract is colonized by organisms provided by the mother, who licks the baby's mouth frequently to introduce them.

Humans are colonized by age 3 with many organisms, in obscure ways. One I know for sure is Oxalobacter spp.
(which is killed off by certain antibiotics--and implicated in formation of kidney stones when gone).

You could have a virus. Many cause diarrhea.

So seeing the doctor would be a good idea.

When you have C.diff. I don't think those treatments kill it off completely anyway. No antibiotic kills every single germ...there are always some left behind. Sinus, bladder, lungs etc. included, too.