waking up shaking and cold

hi I am floating in no mans land so I thought id come back to where I started. the GI guy is testing me for porphyria and all sorts of other things that might indicate that and pyroluria. I have been in contact with the porphyria foundation to get advice on how to best catcht those pesky porpherines in the act and they will call me back on monday. I decided to go to a gi guy because that darn back pain hurt in my abdomin too and I remember being in the hospital last oct and complaining about my back hurting severely every time I ate. so I thought that maybe the breathing difficculties and the back pain had been an ulcer all this time along with acid reflux. I had thought that it ws kydney pain radiating at the time because I had a uti then. the gastro was amazed that no one had looked into the stomach factor yet.

i cant sleep anymore because when I dose off I wake up with the sensation that I am falling and my whole body shakes, my arms are cold and I start to shiver and then all of a sudden i feel like I am being sqeezed and my eyes are going to bulge out of my head. i checked my blood pressure at the time
(because yes I keep a blood pressure monitor next to my bed) and it was 85 over 47. my blood pressure is always low however. is this blood pressure, thyroid, shock?. I know that I am anemic and my iron serum has been low could it be that? wtf