I agree, it's probably a yeast infection. This can occur frequently if you are sexually active due to yeast build-up or your partner not keeping clean enough. I would get some Yeast medicine (monistat or the like) and use it as soon as you can. Also for the lips itching vagisil is great and works immediately!!! Good luck!
It could be a yeast infection. You need to go to any store and get a yeast infection kit. If that doesnt relieve the itching in like an hour go to the Doc.