Dark brown periods

I have been diagnosed with PCOS since May. I need to know if it could affect the colour of my periods as well.

My last three cycles, I have had brown spotting for 3-5 days followed by another half a week of dark brown/blackish periods (in total periods lasted 10 days on a 32-40 day cycle). I'm not on any medications or supplements and no other condition to my knowledge.

I'm currently on day 36 and have had brown spotting since last Thursday and pinkish spotting on Tuesday (accompanied by quick sharp one sided pelvic pain that alternated between the left and right). The flow is very very light, so light I could wear one panty liner the whole day and it would not soak it (for hygienic reasons I change it obviously).

I'm going to contact the doctors tomorrow as I'm currently fed up with it. I haven't had red period in a long time. Does anyone know what could be going on?