Hello. I'm suffering from a vaginal itching, missed period and pain in urination. My partner and I were sexually active and we're not using condoms during sex. I also did the pregnancy test and it resulted negative. What do you think I'm suffering right now? What should I do?

#1: possible yeast infection, UTI (urinary tract infection) or STD (sexually transmitted disease). The second and third require a doctor or nurse clinician.
#2: birth control is needed unless you are planning on a baby. A test can be negative because it's too soon or for a variety of reasons.
#3: stop having sex until you know the cause and have treated it, and if it's STD, don't have sex with that partner until he is treated and cured.

There's an infection, maybe UTI (Urinary Tract Infection) for the better ask an expert for the said situation on yours, both of you consult an expert.