What Causes Loose Motions?

I have watery stools sometimes 3-4 times a day (not every dqa) I have started having low abominal pain no fever or nausea I have had a GI workup last year with clear colonoscopy and labs including stool samples - I have since gone to lactose-free milk I have started having itchy skin in the last week Am I going crazy or do you have any recommendations?