Quick Onset (10) Seconds) Of Extreme Dizziness, Weakness, Followed By

Quick onset (10) seconds) of extreme dizziness, weakness, followed by unconsciousness. At this point possibly not breathing. Also red skin color, sweating, hot. After regaining consciousness, vomiting, not able to move much, difficulty talking. EMT found all vital signs normal. Hospital found no ecg abnormalities. All bloodwork normal. Hospital provided IV fluids. It was 4 hours before I improved much. Six hours before I could stand. Could this be possible food allergy? (apple cinnamon cake eaten 10 minutes before onset) Possible short attack of angina? Hospital suggested dehydration.