vagina itching on the inside?

I have been itching real bad on the inside of my vagina. I have no discharge or no funky smell I thought it was a yeast infection so i bought some monistat and have been using that for 3 days now (I know you use it the full 7days) but right after i put the cream in it starts itching again and seems more irritated than it did before i applied it. The itching eventually goes away and im good again..What can this be?? I know women experience itching on the outside of the vagina but on the inside??