Suggest Treatment For Severe Itchiness In The Labia Majora

Hi,
For the last several weeks, I've had excessive itching down on my labia. I've used vagasil, yogurt, but nothing really took it all the way away. It continues to come back. I've also had a lot of white discharge. Today I noticed some purple colored spots on my labia. They are very small and not raised up from the skin.
I'm wondering if it's time to take this in to my gynecologist, or if this isn't something to be terribly worried about. I tried googling and got various results.
Thanks.