Late period

I’m a little concerned. I was suppose to have my period on the 13th of October but instead I got it on the 26th and I wasn’t bleeding red it was brown, today’s nov.9 and Im still “bleeding” Brown. I’ve also been feeling sick getting nauseous and throwing up, a few months ago I was told I had a cyst but I wasn’t really feeling any of the symptoms, could it be my cyst?Can someone help ? Should I go see a doctor?