Brief Answer:
might be gastroenteritis, symptomatic treatment

Detailed Answer:
Hi XXXXXXX
Welcome
I have gone through your query.

I would like to know few more information like
How many episodes of diarrhoea in a day?
How is the consistency?
Is there any associated nausea, vomiting?
Have you had any out side food? Fast food?
You have mentioned about milk, is this problem occuring for the first time? Or have you experienced it before with consumption of milk?

Based in the information I feel it might be gastroenteritis, so I would suggest you few measures that will be helpful.

You need to follow both pharmacological and non pharmacological measures -- Avoid excess consumption of tea/ coffee/ hydrogenated drinks. Avoid smoking and alcohol, if any.
Antacids like Digene or Gelusil syp, 2tsp in 50ml of water three to four times a day half an hour before food.You can also take capsule omeprazole 20 mg once daily empty stomach, before breakfast for a week.
You can take probiotics like Sporolac or Ecobion which will be beneficial and you can take curd as well.
Eat frequent small meals instead of heavy ones and do not starve.
Avoid spicy and oily food for few days till the symptoms are resolved. Avoid or reduce the intake of meat, dairy products ( milk for few days), and add more fiber to your diet. Eat lots of salads, vegetables, fresh fruits,
Avoid gas producing foods like peas, cabbage, legumes, etc. Eat light meals prepared under hygienic conditions. Avoid eating fast and talking while eating.
I would suggest you to drink plenty of water or electrolyte solutions to prevent dehydration. Add bland foods to your diet, such as bananas, toast, oatmeal and rice in small amounts every couple of hours.
If the symptoms persist or increases in intensity, I would suggest you to get an stool examination done.

Follow this measures your symptoms should reduce.
Hope this helps.
Take care

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