PCOS and when to test?

Alexis

I took birth control for a year and when I went off of it I had regular cycles the past eight months. This month I’m on cycle day 36 (my period should’ve came about four days ago.) throughout the month uterus twitches ,heartburn, somewhat heightened smell, and in the middle of this cycle I had the slightest amount of brown spotting. Today I had stringy discharge as well. When should I take a test? Pcos is so unpredictable. I could be imagining things...but want to be hopeful.