If i took a probiotic while taking antibiotics like flagyl will it decrease my risk or stop me from getting a yeast infection after i'm done ?

YES: Yes, that is one of the main reasons to take probiotics. I advise all my patients take probioitics both during and after antibiotic therapy and feel every doctor should do so as well; it is irresponsible to not do so! along with acidophilus and bifidus it is wise to take sacchromyces boulardii, a probiotic yeast proven to reduce the incidence of antibiotic-associated diarrhea.