Confussed.....need some advice

I am 4 late....before my period was suppose to start I had headaches and these horrible cramps from my lower stomach to my private it only last about 20 minuets and then I was fine. I am now having a little nausea peeing more and having the urge that my cycle is going to start but nothing and I have fatigue spells ( example I get really tired like my blood pressure is up and I get hot flashes) after about 15 minutes I'm back fine.