I got a really heavy period in the middle of the night for just one day?

IVE HAD UNPROTECTED SEX WITH MY BF. MY PERIOD IS ABOUT 2-3 WEEKS LATE. LAST NIGHT I WAS SLEEPING. OUT OF NO WHERE I WAS BLEEDING REALLY HEAVY IN THE MIDDLE OF THE NIGHT. SO I GOT UP AND CHANGED EVERYTHING. BUT THEN WHEN I WOKE UP THIS MORNING IVE BEEN HAVING THIS DARK BROWN THAT ISN'T REALLY HEAVY ANYMORE. WHAT CAN IT BE? AM I PREGNANT? OR IS SOMETHING WRONG WITH MY BODY? I MEAN I DONT FEEL ANY SYMPTOM OF A PREGNANT WOMAN. I MEAN IVE BEEN HAVING SOME BACK PAIN AND MY BOOBS HURT A LIL BIT. BUT THIS ALWAYS HAPPEN WHEN IM BOUT TO GET MY PERIOD. BUT THIS IS THE FIRST TIME THIS HAPPEN. I MEAN HOW COULD I JUST BLEED ALOT IN THE MIDDLE OF THE NIGHT AND NO MORE FOR THE WHOLE DAY TODAY?
Answers:

Girls: Why you girls shaking your bum, what you really want by shaking your bum?

Brown blood is in recent times aged blood. This bleeding episode that you have for sometime and later go lighter could be an indicator that your spell is coming.

I would recommend checking near your doctor as powerfully to see what they utter.

Where can i find a form of birth control that doesn't manufacture me gain immensity? (besides condoms and Abstinence)

You could possibly be getting your spell are within could be something seriously wrong. You should probably see a doctor.

anyone survived an ed at boarding arts school?

flows do rework once within a while
its fine

What is the best doctor for a woman?

Go see your doctor. Unusual bleeding similar to that could be a few problems from sexually transmitted infection to cancer!