hi, the first day of my last period was the 11th of August. I do have the paraguard iud.. overall, my periods have always been regular. i never missed periods, although occasionally they seemed a day or two off but that could have been my own miscalculation at the time. my period has not arrived and today i have only had mucus type spotting with light red blood and only when i wipe. I took a pregnancy test this morning as well as yesterday, both were negative. what could this mean?