the advice about the new soaps and stuff is good, if you have started using even a different body wash or laundry detergent it could cause uncomforatable reactions to the chemicals they use for scenting or color. Also, the yeast infection thing is good as well. Try monostat before going to your doctor, it may save you a little money. If it doesnt ease up or go away, then it may be a UTI and you will need antibiotics for it. But, when your doc gives you your antibiotics, finish the WHOLE bottle, or you will be battling this for a long time to come. they give a set number of doses for a good reason, if you dont take them all, then you are merely setting yourself up for a reoccurance.
It might be a yeast infection are you having any discharge??
If it persist I would call your doctor it could be BV or a yeast infection which is totally normal in a woman.
are you using any new soaps, bath gels, new laundry detergent, fabric softeners, toilet paper? sometimes these things can cause the irritation that you are talking about due to the scents/perfumes.