Why Am I Getting Upper Back Pain And Having Itchy Skin?

Hi, I have been having very itchy skin and its worse at night and I want to get up to have a hot bath. Sometimes the bath helps but by then I feel the hot soak has helped me to sleep. I also have been expereincing high upper back pain that sometimes goes around to my front like a vise grip around my upper body just below mt bra strap. I have bouts of nausea also and low blood pressure. I also get rewd cheeks and I dont know if my blood pressure is upr not when this happens. I awoke from a nap today and noticed my cheeks flushed?