pregnant maybe maybe not

I think I might be pregnant I've been having cramps and nausea for 2 weeks and my period is supposed to start today but I've been hoping to be pregnant but it never happens but this time feels different I had a pregnancy test on Monday that was negative but they said it was too early to tell I don't know if I'm pmsing or actually might be (August 1st was the 1st day of my last) PLEASE HELP