It sounds like you could have a low grade
yeast infection or even an allergy. If you have a
yeast infection, you may want to consider looking into a candida diet (link below). This diet has been helpful in people who have chronic health conditions anyway, so I highly recommend it:
http://altmedicine.about.com/od/popularhealthdiets/a/candida_foods1.htm
Also, I know of a natural formula that targets yeast. If you are interested, let me know and I will send you the link via PM (private message).