Profuse watery diarrhea is most certainly not normal in patients of any age. The differential diagnosis for diarrhea includes allergic, anatomical, autoimmune, endocrine, infectious, and neurologic abnormalities. From the history that you have provided, it is nearly impossible to even narrow down the diagnosis. However, acute onset of watery diarrhea could very well be infectious or allergic in origin as the other causes don’t normally manifest as acute as you are describing.
Either way, this situation is best handed by your primary doctor as (s)he can be able to accurately work up your condition and treat you. As an accurate medical history is the paramount in helping your physician diagnose your condition, be sure to inform him/her of any other symptoms, recent travel, recent lifestyle changes (diet, pets, living/working conditions, etc.), recent fevers/illnesses, current medications, current medical/surgical history, etc.
