Hello, Thanks for your query. If your stomach cramps have started recently and you also have diarrhoea, the cause is probably a tummy bug (gastroenteritis). This means you have a viral or bacterial infection of the stomach and bowel, which should get better without treatment after a few days. A common cause of gastroenteritis is a norovirus. Severe stomach cramps and diarrhoea that make you feel very ill (for example, causing chills or a fever) could be due to a more serious infection, such as food poisoning. This also usually gets better on its own without treatment. If your stomach cramps and diarrhoea continue for more than a few days, you may have a long-term condition, such as irritable bowel syndrome. I do hope that you have found something helpful and I will be glad to answer any further query. Take care