After eating out on Sunday, I had severe diarrhoea and stomach cramps. I am now eating ok, but stools very loose. Is this normal after this?

On the mend? Depending upon the nature of your food poisoning, particularly if an invasive bacteria was involved, you can experience post-infectious irritability (some use the term post-infectious irritable bowel syndrome). Of course, persistence of symptoms warrants evaluation to rule out other pathology that needs treatment. May also consider: food allergy or previously unsuspected food intolerance here.