You may be having candidal vulvovaginitis.
It is a candidal infection caused by Candida albicans.
It is a contagious disease , in your case it might be due to sexual contact.
Clinically , it is diagnosable condition. However , it may be confirmed by microscopic examination of swab taken from affected area.
Antifungal tablets like ketoconazole
and cream like clotrimazole
may improve the disease.
Avoid soap bath, dettol
can be used.
and other diseases may be ruled out.
I hope you got my answer.
Dr. Ilyas Patel MD