My Wife Experienced Extreme Pain - Which She Identified As

My wife experienced extreme pain - which she identified as lower left abdominal; shortness of breath, cold sweats & an acute sense of dread while defecating last night. This is the 3rd time in 4 years that this has occurred but last nights was the worst of the three. She thought she was having poisoning symptoms but I don't think so. Others ate the same food with no issues. The episode was on-going, even after leaving the toilet. Her symptoms did improve after 30 minutes or so. During the episode she thought she was going to die. After I got her in bed she was able to sleep and is fine this morning, (no pain with abdominal pressure) . Once reclined last night her blood pressure was 98/70, pulse 75 then subsequently 65. No fever. She is 26, not pregnant, 2 children, slim but not athletic and generally healthy. Confused as to what this could be?