First negative peestick of the month

Since I'm leaving on Sunday for six weeks, and in case I'm pregnant I would like to see the doctor before I leave, I thought I had a good excuse to do a pregnancy test this morning, three days before my period is due. I didn't, I just wanted to see if I'm pregnant or not. Pretty silly from me, it was obviously negative. How wouldn't it be, considering that the first time around they kept coming back negative even when I was three weeks late? Oh, gosh. It will take a couple of weeks to know...