You need to see a Gyno. I know that vaginal health issues can be embarrassing, but the vaginal health can affect the health of your entire body. If you're in that much pain, MAKE. AN. APPOINTMENT.
In the mean time, you need to check for all of your symptoms. So far, you described a Missing Period, and pain.
When you talk to A DOCTOR, you're gonna have to describe it better. They'll ask you questions like, "What kind of pain?" So there, is it achy or sore or burning or cramping or something other than just "hurts". The more descriptive the better.
"Whole entire private parts" okay you don't have to explain on here, but when you talk to YOUR DOCTOR, you'll have to be more specific. Is the pain INSIDE of you? That's your vagina. Is the pain on the inner or outer lips? Is there a rash or itching? Redness?
Additional things to be able to tell them: Eating habits (this could quite possibly be a yeast infection, just really bad), sexual activity (including oral, vaginal, anal, mutual masturbation, anything where someone else's fluids could have touched your privates), discharge (color, consistency, etc)
Okay, now I'm assuming you're gonna call the doctor. PLEASE do. But until the appointment happens, you need to make sure of a few things:
NO tight pants. Skirts are better, they let your lady parts breathe more
NO underwear that has ANYTHING but a cotton crotch. Breathing thing again.
NO washing your privates with soap. NEVER do that, only a washcloth with warm water.
NO masturbating (and if you have ANY sex toys, clean them thoroughly)
NO bubble bath stuff (bad for your privates)
NO baths, for now stick to showers
NO douching, ever because that's horrible for your vagina
CUT BACK on sugars. My best guess is that you have a yeast or BV infection that has gotten bad. Both are easily taken care of, and are very common (they're not STD or STI's either so don't worry) but a diet high in sugar encourages them.
PLEASE go to the doctor, get checked out, and feel better soon.
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