Could I be pregnant?

So three weeks ago my fiance and I had unprotected sex. It happened several more times after that. Mind you we've been together for more than six years and this is the first time that we've done it unprotected. Right now I'm supposed to have my period in five days but so far I feel a little stomach cramps and some nausea. I would be so happy if I get pregnant. Just thought I would share. I've been crazy HCG pt tests but so far it still says negative. I know I'm testing to early but lol