My period was 22 days late until 2 days ago when I finally got it. I took two pregnancy tests before that, which both came out negative (my boyfriend and I are NOT ttc).  When I first got my period it was a dark brown and then started coming out a dark red, which is pretty normal. This morning though I woke up and took my menstrual cup out to find very thick blood with clotting and also this grey mucus-like discharge inside of the cup. I haven't been feeling any pain, which is a little abnormal because I am used to having cramps. During the days that I did not have my period I was cramping, but not anymore. I just need to know why I all of a sudden have this grey discharge in my period after missing my period for so long.

I also might add that I have not been to the GYN since August 2013. I know I should be going yearly but my insurance makes it hard to switch. My mother was diagnosed with endometriosis before her pregnancy with me and had to get a hysterectomy afterwards due to her ovaries becoming the size of grapefruits. So, I am a little paranoid about getting endo (you're 10x more likely to get it if your mother had it) and would like to know if this is associated with it at all. 

Thanks :)