Ok so there are a bunch of different possibilities here for what could be causing your vaginal itching:
Bacterial infection - The vagina naturally has bacteria in it. I know, gross, but I found that out in sex ed and apparently it's no big deal. Only SOME bacteria are bad and harmful. If you have the harmful kind, this could be the thing behind your itching.
STD - anything from herpes to chlamydia could cause the symptoms you're talking about if you've been putting yourself at risk and having unsafe sex lately, then the only thing to do would be to get yourself tested quickly!
My advice would be to seek medical advice over trusting what you read in forums though.
