Thanks for posting your query.
With the available described symptoms, you are most likely suffering from acute viral gastroenteritis
Presence of watery diarrhea, pains and abdominal symptoms suggests the diagnosis.
Myalgia is an integral symptom of viral infection.
You should consult with internal medicine specialist and should go for thorough check up.
You should take complete antibiotic course, probiotics, proton pump
inhibitors, and antispasmodics.
You should go for complete blood count
You should avoid milk and all milk related products.
You should maintain your hydration and take potassium rich supplements.
Dr. Mayank Bhargava