Masturbating is completely normal and natural. You shouldn't worry about it. Keep doing it and you will see nothing bad happened when you masturbate. Regular masturbation is healthy & it keeps the testes active & more fertile.
Masturbation is a natural habit. If you do not masturbate night falls are natural and harmless. If you are sexually aroused naturally ( not by artificial means) you may do masturbation. Tips; Do it with lubricated hand. Do not stop breathing. Do not do on prone position.By not doing masturbation, if you feel alright, do not masturbate.Do not worry about night falls....... You eat less in dinner.