Help, so confused

Ok so Im 14 passed my missed period, I took 3 test this morning (1 first response and 2 clear blue test one digital and one regular) all said negative...Could I still be pregnant and just not have enough hormone to show yet? Is it possible to drink to much water/gatoraid and dilute it? Has anyone else had this problem and turned out they were? I just would like some advice. I have alot of symptoms like morning sickess, smell aversion, slight mood swings, sore heavy breasts, my jeans and bra just dont fit right, Im not sleeping very well, and I feel like Im thirsty alot.