Help me please

Melanie
I was on my af for 12 days which was very abnormal 6 days after af I started spotting I have spotted for 10 days I was suppose to start my af today acording to glow but I had not all day than tonight my husband and I had sex after words I started spotting and than went away again I have taking a test it was negative but if I go to when I normally start my af if would not be tell Sunday but I'm trying to go off what glow says I have always had normal periods and never have had any kind of spotting between anyone know what it could be