What to do... HELP!!!

So my af was supposed to start on 12/5 and still is a no show. I have had no symptoms of either af or pregnancy. My last pregnancy before I found out I was pregnant I suffered from very painful ovarian cysts and back pain (thank you PCOS) last night I was laying in bed trying to sleep when all of a sudden BAM!!!! I was hit with severe lower abdominal pain that literally put me in tears. It came with nausea and lower back pain and lasted all night long. Throughout today I have had pain in the same lower abdomen but not as severe. I thought "well, here comes af" but nothing still. I'm starting to think maybe it is another ovarian cyst. My question is should I go to the er for a blood test. My obgyn can't get me in until the new year. Help!!!