Hello. Welcome to hcm.
is safe way of pleasuring self with out risk of STD's. When the habit is under control and when there is no addiction to it,it will not have any side effects,either now or later in life. Many studies have shown beneficial effects too. As the sperms are removed,new sperms are produced and can maintain a proper cycle,if not,old sperms remain and may later leak out at night.
I adivce you to stop worrying and continue unless you are too addicted to it. You are eligible for marriage and will not have any ill health.
All the best