Yesterday morning I woke up with pain between the shoulder blades (more towards the right side), and then felt quite sick for about the next 20 minutes - nausea, breathlessness, cold sweat, fever, etc. I was fine after that, just somewhat tired for the rest of the day. I have low blood pressure, not high, but I wondered if it sounded like something to do with the heart. I've also had symptoms that seem to indicate an autoimmune problem - does it sound more like it would be related to that? Thanks for any opinions.