You should speak to your doctor about
this. I have a mirena coil in and haven't
had a period for moths but when I had the
copper coil in my periods were heavy yet
irregular.
If you have had a negative pregnancy test
then chances are you're not pregnant
this website says a possible side effect
of paragaurd is delayed menstration
http://www.C
ontracept.Info/iud-paragard.Php
(change all letters to lower case)
so perhaps that is what this is.
Good luck!!!