What if I use monistat with out a yeast infection?

Fazeela
The other day I saw a cottage cheese like discharge. Today it was normal. However, my vagina feels a little itching.
I think it is a yeast infection tho 
Like almost everyone I have my period or around that time for the past 2-3 months it gets itchy down there. Last time I got my period ( I have irregular very frequent period) I saw the white stuff on my tampon. And around that time my vagina was super itchy and had like red itchy spots