Hi. Im A Highschool Senior Student. I Drink Lots Of

Hi. Im a highschool senior student.
i drink lots of water (3litres a day) for my acne and my own health. During exams i feel completely ok.. and when the exam finishes or its gona finish in a couple of minutes i start to ejaculate or i feel im gona ejaculate.. im a boy just to be clear.
it all started happening to me when i started to drink that amount of water.