Help!

Ahliyah

So. I was three days late on my period and it was really sketchy. It's been going from heavy to nothing since Monday when it started. Now it's gone and I've been about ready to pee myself out of nowhere every two hours. And I'm usually a I pee only like three times a day girl. Before my "missed period" I had been real nauseous and tired and had no period symptoms. I even had slight cramps and implantation bleeding. What could this be?