Are you asking if this is an STD?
I mean, it could be. It could also be yeast or bacterial vaginosis. The only way to know is to see your doctor and get some testing done. There's no way anyone online can tell you what this is - the symptoms of all of them are very similar and the only way to know is to see a doctor. An urgent care, Planned Parenthood, STD clinic or any walk-in clinic or health department will be able to help with this.