It's normal process cause if anything will be more in the body then it's will flow out .
At your age generally due to harmone and some physiologically process formation of sperm is in the good condition and it can be flow out through the route of penis .
Next Steps
You should attention your brain in the creative work and study so that dream will be not occur and ejaculation of sperm will not occur as you are getting now.
Health Tips
Please follow good life style as take plenty of fluid and take less spicy and fatty foods and
do exercise regularly with yoga and meditation and
keep positive attitude to fight any disease and any problem of your life.