Mum just made both of us a ham salad with coleslaw and potato salad that we got from the supermarket. Both the coleslaw and potato salad tasted fine, slightly tangy but they are most of them time. When I took my plate out I saw the date on the coleslaw and potato salad was the 23rd december. I had a spoonful of each, am I likely to get sick? How do you know when things like that aren't good to eat?