I would test again, your levels could have just needed time to rise. If its still negative I would go to the doctor to see what's causing the wierd light periods.
I had a test done a few days back and it was negative
pregnancy test asap.. it bappent to me i tough it was my period but it wasnt any more. i went to doctor thinking i was maybe like 2 3 weeks no more than a month sens i had a period a month before but very wierd, but omg i was ctually 9 weeks playing soccer goin to gym and drinking like crazy. never tough i was pregnant.. i had that brown discharge for 3 days and doctors will say my baby was not gonna make it.. and now im due in 2 weeks..
Take a pregnancy test. It sounds like your last period could have been implantation bleeding. Good luck.