Amazingly, you sound like one of us! Gastroparesis or delayed gastric emptying is very common with dysautonomia/EDS, as is neurogenic shock when lying on our backs (heart rate and blood pressure dive simultaneously and we become ‘paralyzed’. It is very frightening and has happened to me many times. It sure sounds like you have high intracranial pressure. Because lumbar punctures aren’t recommended for EDS patients (I’m assuming you’re hypermobile here!) a trial with Diamox to relieve the pressure can help diagnose it, as long as your head MRI shows no apparent abnormalities (brain tumor, pituitary tumor, etc). You may first want to have your electrolytes checked (your serum CO2 needs to be at 22 or above for Diamox to work). If you’re in the clear, a night-time dose of about 250mg (not the Sequels) should eliminate the headache/pressure feeling over-night! If so, then you can at least get rid of those assorted symptoms! I’m working on our gastroparesis/organ dysfunction now. Hang in, my friend.