Hi.... Welcome to healthcare magic. As per your complain you have problem of abdominal problems and change a consistency of stool that may be because of gastroenteritis problem or food intolerance or other condition. Irritable bowel syndrom also lead to alternative diarrhea and constipation problem. Lack of water and high fiber foods also cause loose stool. Stool sample test is helpful to detect any infection present or not.. Colonoscopy is helpful for further diagnosis. Consult a gastroenterologist for further diagnosis. Detail history and investigation give exact idea about problems. I hope my guidance helpful to you.. Take care. Thank you.