Sorry to hear that Nobot. You should be very careful with meats. Fish that goes past its date can be dangerous. Always check the expiration before consuming.
Since that is too late, make sure you have a bucket or something near by just in case. You might be fine. If you think you are going to be sick, your body will make itself ill; the mind is a powerful thing. So don't expect to be ill, just remain cautious.
If you do become unwell, be sure to consume water slowly but regularly to prevent dehydration (that is the main concern when one gets food poisoning, and what kills people). Also don't use the computer if you are sick, it won't make you feel any better.
You may want to lay on your side (this can help reduce nausea, I forget why but I was recommended this by a doctor when I had a spout of illness many years back).