I doubt seriously that this accident will ruin all of your progress. It’s possible that it may set you back, but there’s no way of knowing yet. I don’t know where you are with the treatment, but if you’re taking antifungals or probiotics, you might think about upping the amount of one or the other or even both for a few weeks just to be safe.
The safest form of yogurt of course is to make your own, and some stores such as Amazon carry yogurt makers which makes it a lot easier. If you have to purchase commercial yogurt, I would stay with the unsweetened plain, organic Greek yogurt; but even this can cause problems in some people so start slowly with only a few bites.