Question about yeast..?

I've never had a yeast infection before. But I've been on antibiotics and since I started taking these pills my vagina has become very irritated and itchy. I haven't had any odor or discharge though? I bought the Monistat thing from Walmart that is for yeast infections but I'm just not 100% sure if that's what It is or not.
My mom tells me to use the Monistat because it is a yeast infection, I just want some other opinions