Sorry to hear about this, and I'm glad you didn't hurt yourself by passing out.
You should find out whether your blood test results revealed hemoconcentration and hypoalbuminemia. If so, in conjunction with hypotension, you probably had an episode of SCLS; if not, you probably didn't.
If your clinical and blood results are consistent with an episode of SCLS, ask for the hospitals to send your episode blood samples to Dr. Druey at NIH for his conclusive analysis -- today, before they throw it out. For further shipping and delivery instructions, have them call his office, because the blood must be chilled but not frozen.