Yeast infection?!

Okay guys I need HELP. I am 99% sure I have a yeast infection. I’ve had them before but NEVER this intense. I’m so itchy, and my vagina feels like it’s inflamed or something! My doctor ordered me diflucan (antifungal) to take. I took one dose last night and it feels a little better, but I’m supposed to take one every three days. I guess what I’m asking is has anyone experienced a yeast infection like this or do you think it’s something else?!