What will happen if I can't drink enough water for a long time?

Yes see a doctor and psychiatrist!!! U must deal with both physical and mental health!!!!

I'd check with my doctor. Perhaps you can sip through a straw throughout the day, so you don't become dehydrated.

Maybe the fruit you ate, and the porridge you had, contain enough water. There are such people around me, and she seldom drinks water. But she's healthy.

Dehydration

You can get your fluids other ways also. Juice, soup/broth, sucking on ice cubes. You can make water a little more bearable to drink by adding lemon or lime juice to flavor it. Take small sips. Can you drink through a straw without incident? Eating Watermelon is very good for getting water, but you need to eat a lot of it to get your daily requirement. 300ml is not enough. If none of the above suggestions are helpful then you need to see your doctor. (Feeling thirsty is a sign that you are already quite dehydrated so try to stay above feeling thirsty. That isn't to say it's a good sign if you don't feel thirsty, that is saying you want to keep your body replenished so the feeling of thirst doesn't happen.)