Spotting or period?

Hi all this is a confusing one... I had a mirena coil removed in Jan and have only had two periods since with a 36 day gap, today is two weeks since last period and I think I've got spotting... Bit like a light period but no real cramps or anything... No idea if this is just an irregular period or what. Seems unlikely that it's implantation spotting as if I now have a 36 day cycle then I'm not ovulating for another couple of days... But what is it? Have taken both preg and ov tests and both negative... So confused!!