Coleslaw gave me food poisoning

I bought coleslaw at kfc Eastgate on Saturday 9 September at around 13:30, my order number was 237. I was given a portion of coleslaw that said the expiry date was 9 September at around 18:00. But when I opened it, the coleslaw smelled stinky and off, and the mayonnaise looked like it had become watery and settled to the bottom of the container instead of coating the vegetables. I returned it to the store and got a replacement that had an expiry date of 11 September. It seemed to have a slight smell but not as bad as the first one so I took it to be the smell of cabbage and ate it. I got food poisoning and about 3 hours after I ate it I started having terrible diarrhea and it carried on until the next morning. I was the only one in the family who ate this horrid coleslaw so I know it was the cause. I am truly disappointed at the standard of food hygiene/handling if cold products that are served before their expiry date can be off.