Half of the subjects in a study are given a drink with extra whey protein and the other half are given a drink without whey protein and both groups’ muscle strength is monitored. the drink without the whey protein is called a(n)

From the context of the question, I am going to say placebo. This is me assuming, however, that both groups were told that their drinks had the protein powder

There are a couple of answers.you could have an infection, a sti, std, or other problematic health issues.i would recommend going to the doctors, if not, take a shower and wash down there, then wait a couple of days, and if it’s still there, then is when you should go to the nearest or trusted gynecologist of your choice.